The present invention relates to a device and a system that promote a chemical reaction, and a method for producing the device and the system, and relates particularly to a device and a system that are capable of improving a reaction rate, and a method for producing the device and the system.
Every chemical material is composed through a chemical bond, and another material is newly produced by cleavage and formation of a bond, that is, a chemical reaction, and then processed. Rate of a chemical reaction is governed by activation energy, and as a background art, there are only two means capable of increasing a reaction rate: inputting heat overcoming activation energy and using a catalyst reducing activation energy by changing a reaction path. However, heat input increases an energy cost, and also inadvertent heating generates some unnecessary and hazardous by-products, and therefore there is a limit to use of this means. Further, use of a catalyst requires rare metals and expensive chemical and also in most cases, a specific catalyst is effective only to a specific chemical reaction and therefore there is an issue in terms of versatility. Accordingly, in view of realization of a sustainable growth society in the future, a new means promoting a chemical reaction is sought.
As a new method of controlling a chemical reaction, for example, Patent Literature 1 (PTL1) discloses a method of using a coupling between an electromagnetic wave and a matter. Specifically, the method mainly includes a process of bringing a reflective or photonic structure including an electromagnetic mode resonant with a transition in a molecule, a biomolecule, or a material, and a process of arranging the molecule, biomolecule, or the material inside or on the aforementioned type of structure, the method further including controlling a chemical reaction by affecting at least one of criteria or parameters of the reaction (reactivity of a material to be involved in the reaction, kinetics of the reaction, a rate and/or a yield of the reaction, and thermodynamics of the reaction) through use of coupling of the molecule, the biomolecule, or the material with a local electromagnetic-vacuum field, and then resulting rearrangement of an energy level of the molecule, the biomolecule, or the material.
However, the aforementioned method of controlling a chemical reaction has an issue as follows.
As described above, the issue with the background art is that there are only two means available for promoting a chemical reaction, the means wastefully using a large amount of energy in order to overcome activation energy and consuming scarce resources by using a catalyst decreasing activation energy by changing a reaction path. The reason is that, within a framework of a chemical reaction theory in the background art, a means of quantitatively reducing magnitude of activation energy is not known, and therefore the two means are selected as a logical conclusion under the present conditions.
On the other hand, aforementioned PTL1 discloses a method of using a coupling between an electromagnetic wave and a matter as a means of overcoming the issue with the background art. However, PTL1 does not indicate a theory of connecting a physical phenomenon being a coupling between an electromagnetic wave and a matter to a chemical phenomenon being a reaction, and therefore it is impossible to quantitatively evaluate an effect of a coupling between an electromagnetic wave and a matter on a chemical reaction. Accordingly, a degree of an effect of a coupling between an electromagnetic wave and a matter when being actually used in a chemical reaction is totally unknown, and it is even unknown whether the coupling promotes or suppresses the reaction. Consequently, it is impossible to design a specific device, and therefore an industrial use is hindered.
An object of the present invention is to provide a chemical reaction device capable of promoting a chemical reaction, and a method for producing the device.
To achieve the above-mentioned object, a chemical reaction device according to the present invention comprises an opto-electrical field confinement chemical reaction container structure integrating an opto-electrical field confinement structure forming an optical mode having a frequency identical to or close to a vibrational mode of a chemical material related to a chemical reaction with a chemical reaction container structure including a space for storing fluid required for the chemical reaction including the chemical material, wherein
a chemical reaction is promoted by vibrationally coupling the optical mode with the vibrational mode.
A method for producing a chemical reaction device comprises:
producing a structure including a mirror plane/substrate by fort a mirror plane on a substrate;
producing a structure including a protective film/mirror plane/substrate by forming a protective film on the mirror plane;
producing a structure including a spacer/protective film/mirror plane/substrate by arranging a spacer defining a cavity length on the protective film;
producing a Fabry-Pérot cavity structure including a substrate/mirror plane/protective film/spacer/protective filet/mirror plane/substrate by laying a structure including the protective film/mirror plane/substrate on top of a structure including the spacer/protective film/mirror plane/substrate; and
producing the chemical reaction device by housing the Fabry-Pérot cavity structure in an enclosure including an inlet, an outlet, and a chamber for storing the Fabry-Pérot cavity structure.
The present invention can promote a chemical reaction by reducing activation energy of the aforementioned chemical reaction.
Before describing specific example embodiments and examples of the present invention, the present invention will be surveyed.
A device as an example of the present invention is a chemical reaction device including
an opto-electrical field confinement chemical reaction container structure integrating
an opto-electrical field confinement structure forming an optical mode having a frequency identical to or close to a vibrational mode of a chemical material related to a chemical reaction with
a chemical reaction container structure including a space for storing; fluid required for the chemical reaction including the chemical material, wherein
the chemical reaction is promoted by causing a vibrational coupling between the optical mode and the vibrational mode and reducing activation energy of the chemical reaction.
A method for producing a chemical reaction device as an example of the present invention includes:
a process of producing a structure including a mirror plane/substrate by forming a mirror plane on a substrate;
a process of producing a structure including a protective film/mirror plane/substrate by forming a protective film on the mirror plane;
a process of producing a structure including a spacer/protective film/mirror plane/substrate by arranging a spacer defining a cavity length on the protective film; and
a process of producing a structure including a substrate/mirror plane/protective film/spacer/protective film/mirror plane/substrate by laying the structure including the protective film/mirror plane/substrate on top of the structure including the spacer/protective film/mirror plane/substrate.
Another method for producing a chemical reaction device as an example of the present invention includes;
a process of producing an acid-soluble-glass-filled glass tube by filling acid-soluble glass into a glass tube,
a process of producing a thinned acid-soluble-glass-filled glass tube by drawing the acid-soluble-glass-filled glass tube in a tube-axis direction by heating;
a process of producing a thinned acid-soluble-glass-filled glass tube accumulation by aligning one or more of the thinned acid-soluble-glass-filled glass tubes in such a way that tube axes are parallel to one another, and fusion-bonding the glass tubes by heating;
a process of producing a re-thinned acid-soluble-glass-filled glass tube accumulation by drawing the thinned acid-soluble-glass-filled glass tube accumulation in a tube-axis direction by heating, and applying pressure in a direction perpendicular to the tube axis as needed;
a process of producing a re-thinned glass tube accumulation by causing the acid-soluble glass to dissolve from the re-thinned acid-soluble-glass-filled glass tube accumulation by acid;
a process of producing a linear cavity accumulation by forming a mirror plane inside each re-thinned glass tube constituting the re-thinned glass tube accumulation, and forming a protective film on the mirror plane as needed; and
a process of producing a chemical reaction device by housing the linear cavity aggregate in an enclosure including an inlet, an outlet, and a chamber for storing the linear cavity aggregate.
The aforementioned chemical reaction device and methods for producing a chemical reaction device as examples of the present invention bring the following effects.
The first advantageous effect is that, by vibrationally coupling an optical mode formed by an opto-electrical field confinement structure with a vibrational mode of a chemical material related to a chemical reaction, the vibrational energy of the chemical material can be decreased and the activation energy of the chemical reaction can be reduced, and therefore a chemical reaction device enabling remarkable promotion of a chemical reaction can be provided.
The second advantageous effect is that, by using a vibrational coupling as a means of decreasing activation energy, a chemical reaction device enabling promotion of every type of chemical reaction, independent of chemical properties of materials that make up the device, can be provided.
The third advantageous effect is that, by using vibrational coupling as a means of decreasing activation energy, a chemical reaction device enabling a chemical reaction requiring a reaction temperature of 1000° C. to be performed at room temperature can be provided.
The fourth advantageous effect is that, by using vibrational coupling as a means of decreasing activation energy, a chemical reaction device enabling tremendous acceleration of a reaction rate by a million times with activation energy of 0.5 eV and by a trillion times with activation energy of 1.0 eV can be provided.
The fifth advantageous effect is that, by using a vibrational coupling as a means of decreasing activation energy, a chemical reaction device enabling a catalytic effect to be maintained up to the submillimeter order being a distance longer than that by a normal catalyst by a million times can be provided.
As the sixth advantageous effect, by modularizing, unitizing, and systematizing a device, taking advantage of a characteristic of a vibrational coupling being dependent only on a structure, a chemical reaction device useful for greatly reducing production/processing costs and greatly improving productivity can be provided.
An example embodiment of the present invention will be discussed in detail below with reference to drawings.
In this section, an example embodiment of the present invention will be discussed.
The example embodiment of the present invention will be described in sequence from a principle of the invention to materialization of the invention in three Items (1) to (3) discussed below:
(1) a process of quantifying a chemical reaction using a vibrational coupling,
(2) a process of materializing a structure satisfying a requirement necessary for a vibrational coupling, and
(3) a process of materializing a vibrational coupling chemical reaction device, and producing and processing a desired chemical material.
[(1) Process of Quantifying Chemical Reaction Using Vibrational Coupling]
First, with regard to Item (1), skillful fusion of a quantum-mechanical phenomenon being a vibrational coupling and a physicochemical phenomenon being a chemical reaction enables tremendous scientific and technical progress that nearly every type of chemical reaction can be phenomenally promoted, and analytical and quantitative evaluation of promotion of a chemical reaction by a vibrational coupling will be discussed according to Items (1)-A, (1)-B, and (1)-C described below:
(1)-A: interaction between light and matter,
(1)-B: a method of describing a general chemical reaction by an equation, and
(1)-C: a method of deriving an equation quantitatively describing a reaction rate constant under a vibrational coupling.
[(1)-A: Interaction Between Light and Matter]
With regard to Item (1)-A, interaction between light and matter will be discussed. When a matter is placed in a structure in which a local opto-electrical field can exist, such as a cavity or a surface plasmon-polariton structure, light and the matter start to have a new dispersion relation with respect to energy/momentum, as illustrated in (A) in
ℏΩR [Math. 1]
and is proportional to a strength of interaction between light and matter. Note that
ℏ [Math. 2]
is the Dirac constant acquired by dividing the Planck constant h by 2π. For convenience of expression, the Rabi splitting energy may be hereinafter described as hΩR. (B) in
ℏΩR [Math. 3]
and energy of the states being
ℏω0−½·ℏΩR [Math. 4]
and
ℏω0+½·ℏΩR [Math. 5]
According to a JaynesCummings model rotating-wave-approximating the aforementioned Rabi model, Rabi splitting energy hΩR is expressed by Equation 1.
where, as described above,
ℏ [Math. 7]
denotes the Dirac constant (acquired by dividing the Planck constant h by 2π), and ΩR denotes a Rabi angular frequency, N denotes a number of the matter, E denotes an amplitude of the electric field of light, d denotes a transition dipole moment of the matter, nph denotes a number of photons, ω0 denotes an angular frequency of a matter transition, ε0 denotes a vacuum dielectric constant, and V denotes a mode volume. The mode volume V approximately has magnitude of a cube of a light wavelength. Important physical conclusions implied by Equation 1 are listed as (1) to (3) below.
(1) Rabi splitting energy hΩR is proportional to the square root of the number of the matter N. In other words, unlike a normal physical quantity, Rabi splitting energy hΩR is dependent on N and increases as N increases. The dependence on the square root of N is derived from interaction between light and a matter being a macroscopic coherent phenomenon.
(2) Rabi splitting energy hΩR is proportional to the product of an amplitude of the electric field of light E and a transition dipole moment d. In other words, interaction between light and matter increases as a structure has a stronger degree of opto-electrical field confinement, and as the matter has a stronger degree of light absorption.
(3) Rabi splitting energy hΩR has a finite value even when a number of photons nph is zero. In other words, a light-matter hybrid exists even in a dark state in which light does not exist at all. The light-matter interaction is derived from being based on quantum fluctuations in a vacuum field. In other words, from a quantum-mechanical view, a photon repeats generation and annihilation in a microscopic space, and a light-matter hybrid can be generated without providing light externally.
A ratio ΩR/ω0 between Rabi splitting energy hΩR and transition energy of a matter
ℏω0 [Math. 8]
is referred to as a coupling strength. A coupling strength ΩR/ω0 is an indicator representing a degree of how much a transition energy is Rabi-split by light-matter interaction. Further, a coupling strength ΩR/ω0 is normalized by transition energy of a matter in an original system, and therefore diverse light-matter systems with different energies can be objectively compared. Roughly speaking, a case of a coupling strength ΩR/ω0 being less than 0.01 is referred to as a weak coupling (Equation 2), a case of a coupling strength being greater than or equal to 0.01 and less than 0.1 is referred to as a strong coupling (Equation 3), a case of a coupling strength being greater than or equal to 0.1 and less than 1 is referred to as an ultra strong coupling (Equation 4), and a case of a coupling strength exceeding 1 is referred to as a deep strong coupling (Equation 5). An observed value of a coupling strength reported to date is 0.73. In other words, a deep strong coupling exists only theoretically under the present conditions, and an actual system includes up to an ultra strong coupling.
[(1)-B: Method of Describing General Chemical Reaction by Equation]
With regard to Item (1)-B, a general chemical reaction will be discussed. In brief, a chemical reaction is cleavage and formation of a chemical bond. For example, a chemical reaction by which a molecule AB is cleaved and a molecule BC is newly generated, where A, B, and C denote atoms, is expressed by Equation 6 below.
AB+C→A+BC (Equation 6)
(A) in
E
a0
=U(a)−U(re)=U(a)+De (Equation 7)
When thermal energy sufficiently matching the activation energy Ea0 is applied, classically, the molecule AB increases an amplitude of the molecular vibration, and quantum-mechanically, it jumps up the vibrational energy levels accompanying the reaction potential AB in a step-by-step manner. Consequently, the chemical bond of the molecule AB is cleaved, followed by the movement to a reaction potential BC passing through a transition state located at an internuclear distance r=a, and a bond is newly generated between the atom B and the atom C. Through the series of processes, the chemical reaction in Equation 6 is completed. Vibration energy Ev of a molecule is described by Equation 8 below.
Note that v denotes a vibrational quantum number,
ℏ [Math. 14]
denotes the aforementioned Dirac constant, ω denotes an angular frequency, k denotes a force constant, and at denotes a reduced mass. A force constant k is also referred to as a spring constant and is an indicator of a strength of a chemical bond. Specifically, when a value of a force constant k is small, vibrational energy Ev is small and a chemical bond is weak. On the contrary, when a value of a force constant k is large, vibrational energy Ev is large and a bond is strong. In addition, under harmonic oscillator approximation, a force constant k is a second differential coefficient at r=re in a vibration potential. Accordingly, a bottom of a vibration potential U(r) becomes shallow when a value of a force constant k is small, and the bottom becomes deep when the force constant k is large.
Next, we will show that the activation energy Ea0 can be expressed as a function of a force constant k as follows: as indicated by Equation 7, the activation energy Ea0 is a function of U(a). When U(a) undergoes a Taylor expansion around re, Equation 9 below is acquired.
where U(n)(r) denotes an n-th derivative of U(r). Note that the above modification of Equation 9 uses the following three facts: first, −U(re) is equivalent to dissociation energy De, as described above, and therefore U(re)=−De. Second, the first derivative of a vibration potential is force and a value thereof is zero at the equilibrium internuclear distance re and therefore U(1)(re)=0. Third, the second derivative of the vibration potential at the equilibrium internuclear distance re is the force constant k, as described above. Combining Equation 7 with Equation 9 and neglecting the third-order term and beyond by harmonic oscillator approximation yields Equation 10 below.
In general, a force constant k is determined by an electronic state of a molecule and therefore is a constant inherent to the molecule and cannot be changed once an elementary composition and a structure are determined. Further, once an electronic state is determined, both an interatomic distance in a transition state a and an equilibrium internuclear distance re are also constant. Accordingly, activation energy Ea0 cannot be changed unless a reaction potential or a vibration potential being a component thereof is changed. However, as will be discussed in the next item, the force constant may be decreased by using a vibrational coupling being a kind of interaction between light and matter. Thus, the vibrational coupling can reduce the activation energy Ea0 according to the relation in Equation 10.
[(1)-C: Method of Deriving Equation Quantitatively Describing Reaction Rate Constant Under Vibrational Coupling]
With regard to Item (1)-C, a vibrational coupling and chemical reaction promotion by a vibrational coupling will be discussed. A vibrational coupling is a kind of the aforementioned interaction between light and matter and refers to a phenomenon of an optical mode formed by a cavity capable of confining an electromagnetic wave in an infrared region (wavelength: 1 to 100 μm) or a surface plasmon-polariton structure being coupled with a vibrational mode of a chemical material such as a molecule or a crystal. In (A) in
ℏω0 [Math. 17]
In other words, when the vibration system (a) resonates with the optical system (c) at an angular frequency ω0, a vibrational coupling system (b) in which light (the optical system) and matter (the vibration system) are mixed is generated. In the vibrational coupling system (b), a vibrational level v=0 is equivalent to that in the vibration system being an original system; however, a vibrational level v=1 splits into energy levels being an upper branch and a lower branch.
Next, vibrational energy of the vibrational coupling system will be determined. By use of vibrational energy of the vibration system being an original system
ℏω0 [Math. 18]
and Rabi splitting energy hΩR, vibrational energy of the lower branch of the vibrational coupling system is expressed by Equation 11a below.
In a similar manner, vibrational energy of the upper branch is expressed by
however, as will be discussed later, a vibrational level of the upper branch of the vibrational coupling system does not contribute to promotion of a chemical reaction and therefore is not hereinafter mentioned. As indicated by Equation 11a, the vibrational energy of the vibrational coupling system decreases from the vibrational energy of the original system
As indicated in (b) in (A) in
Next, activation energy of the vibrational coupling system will be determined. When activation energy of the original system is denoted as Ea0, activation energy of the vibrational coupling system is denoted as Ea−, Equation 13 below is acquired from Equation 10 and Equation 12.
Note that, in Equation 13, we used an approximation that a difference between an equilibrium internuclear distance and an interatomic distance in the transition state is nearly the same between the original system and the vibrational coupling system. Referring to (B) in
As a supplement to this section, the reason for existence of the upper branch of the vibrational coupling system being neglected in the discussion will be discussed. Referring to Equation 13, activation energy Ea+ corresponding to vibrational energy of the upper branch becomes
The activation energy Ea+ of the upper branch is greater than the activation energy Ea0 of the original system, and therefore remaining at the upper branch level slows a reaction compared with the original system. However, a vibrational state of a reactant molecule actually transitions back and forth between the upper branch and the lower branch ΩR times per second (typically 106 to 107 times) in the vibrational coupling system, which is sufficiently faster than a typical reaction rate. In other words, even though the vibrational state hangs around the upper branch level with relatively high activation energy at a certain moment and thereby a reaction is not likely to occur, the vibration state can transition to the lower branch with relatively low activation energy at the next moment, therefore, a reaction is likely to occur. Accordingly, it is concluded that existence of the upper branch can be neglected in considering a chemical reaction in the vibrational coupling system.
Next, a chemical reaction promoting action by a vibrational coupling will be quantitatively evaluated by use of a ratio of a reaction rate constant between the vibrational coupling system and the original system, that is, a relative reaction rate constant. A reaction rate constant is a physical quantity easier to measure compared with activation energy and is also highly practical. Further, as will be discussed later, an expression by a relative reaction rate constant provides various implications in using a vibrational coupling in chemical reaction promotion.
Assuming that, for example, the reaction indicated in Equation 6 is a first-order reaction with respect to the molecule AB and the atom C, respectively, a reaction rate formula of a chemical reaction can be discussed by Equation 14 below.
R=κ[AB][C] (Equation 14)
where R denotes a reaction rate, κ (kappa) denotes a reaction rate constant, [AB] and [C] denote concentrations of the molecule AB and the atom C, respectively. One hand, a reaction rate is defined as a change in a concentration per unit time and has a dimension of concentration/time. On the other hand, the unit of a reaction rate constant varies by an order of reaction, and when second (s) is taken as the unit of time and molarity (M where M=mol·L−1, L: liter) is taken as the unit of a concentration, for example, the unit of a zero-order reaction is M·s−1 having the same dimension as a reaction rate, the unit of a first-order reaction is s−1, and the unit of a second-order reaction is M−1·s−1. A reaction rate constant is expressed by Equation 15 below as a function of a frequency factor A, activation energy Ea0, and temperature T.
where kB denotes the Boltzmann constant. Equation 15 is an empirical formula known as the Arrhenius equation. On the other hand, Equation 16 below is the Eyring equation being one of theoretical formulae deduced from the transition state theory.
While the Eyring equation has various expressions, an equation used in a most basic chemical reaction (a dissociation reaction) is used here. Note that a denotes an interatomic distance in the aforementioned transition state, and similarly, r denotes the aforementioned equilibrium internuclear distance. Next, a ratio between a reaction rate constant in the presence of a vibrational coupling and a reaction rate constant in the absence of a vibrational coupling, that is, a relative reaction rate constant, will be determined. First, by substituting Equation 13 indicating activation energy of the vibrational coupling system determined in the previous section into Equations 15 and 16, respectively, equations of a reaction rate constant in the presence of a vibrational coupling is derived, respectively. Next, by respectively determining ratios to the equations of a reaction rate constant expressed by Equations 15 and 16 for the original system, that is, the case in the absence of a vibrational coupling, Equations 17 and 18 below being equations of a relative reaction rate constant are finally acquired, respectively.
However, in derivation of Equation 17, because a vibrational coupling does not affect a collision frequency of molecules, it is assumed that a frequency factor A takes an identical value between the case in the presence of a vibrational coupling and the case in the absence of a vibrational coupling. Since a ratio of A to A is one, the term of the frequency factor A disappears in Equation 17. Further, in derivation of Equation 18, it is approximated that a ratio between an interatomic distance in a transition state a and an equilibrium internuclear distance re is nearly identical between the case in the presence of a vibrational coupling and the case in the absence of a vibrational coupling. Since a ratio is determined to be one similarly to the above, the term of ((a/re) in Equation 18 is canceled. It is worthy to note that Equations 17 and 18 are equations derived before anyone else in the world as a result of concentrated examinations by the present inventor and are disclosed for the first time by the present invention.
By the theoretical considerations discussed above, we are not only freed from various physical quantities, such as a frequency factor A, an interatomic distance a in a transition state, and an equilibrium internuclear distance re, all of which are difficult to be experimentally measured or difficult to be theoretically estimated, but also can acquire a simple and clear equation expressing a relative reaction rate constant (a ratio κ−/κ0 between a reaction rate constant of an original system and a reaction rate constant of a vibrational coupling system) with merely three physical quantities as parameters, that is, activation energy Ea0 and temperature T being experimentally and theoretically familiar physical quantities, and a coupling strength ΩR/ω0 being the most important indicator of a vibrational coupling. By derivation of Equations 17 and 18, an effect of a vibrational coupling on a chemical reaction can be quantitatively evaluated. In other words, for example, when a vibrational coupling is applied to a chemical reaction, a degree of reaction promotion expected in the target chemical reaction, an effect of temperature, effectiveness of magnitude of activation energy, a type of chemical reaction advantageous to a vibrational coupling, and the like can be previously predicted as objective numerical values. A further advantage of Equations 17 and 18 is that the equations are applicable regardless of a type of chemical reaction. For example, Equations 17 and 18 hold regardless of a phase, such as a gas phase, a liquid phase, or a solid phase, in which a chemical reaction occurs. The reason is that Equations 17 and 18 do not include a parameter limiting a phase. Further, reaction promotion by a vibrational coupling can be accurately evaluated by use of Equations 17 and 18 with respect to a chemical reaction with any order including a first-order reaction, a second-order reaction, a third-order reaction, and any other reaction with a complicated order such as a 1.5-th reaction. The versatility is derived from employment of a relative reaction rate constant κ−/κ0 being a ratio between reaction rate constants of an original system and a vibrational coupling system in the expressions in Equations 17 and 18; and since κ−/κ0 is an abstract number, any reaction can be quantitatively analyzed regardless of a unit. From the above, it can be concluded that Equations 17 and 18 are an exceptionally powerful weapon in designing a chemical reaction device using a vibrational coupling.
Referring to
Assuming that an effect of vibrational coupling on a reaction rate constant is the same as an effect of temperature, that is, κ−=κ*, since Equations 17 and 19 are exponential functions of the same type, Equation 20 below is acquired by comparing exponent parts.
Equation 2.0 is an equation indicating how to convert a coupling strength ωR/ω0 to reaction temperature, implying that an effect of a vibrational coupling with a coupling strength ΩR/ω0 is equivalent to an effect of reaction temperature with a multiplying factor T*/T.
(A) in
Referring to (B) in
(C) in
The first characteristic of (C) and (D) in
The second characteristic is that a relative reaction rate constant κ−/κ0 does not reach 3.0 even when Ea0=2.50 eV where the increasing tendency is largest in the weak coupling region. On the other hand, a relative reaction rate constant κ−/κ0 reaches a maximum of 104 in the strong coupling region. Furthermore, in the ultra strong coupling region, a relative reaction rate constant reaches κ−/κ0=1012 at Ea0=2.50 eV even when ΩR/ω0=0.3 and reaches 103 at Ea0=0.250 eV, κ−/κ0≈106 at Ea0=0.500 eV, and κ−/κ0≈1012 at Ea0=1.00 eV when ΩR/ω0=1.0.
The third characteristic is that a discrepancy is generated between an Arrhenius-type curve (a dotted line) based on Equation 17 and an Eyring-type curve (a solid line) based on Equation 18, as a coupling strength ΩR/ω0 increases. In particular, in the deep strong coupling region, a discrepancy between the both curves increases as activation energy Ea0 decreases, and finally, when activation energy Ea0 becomes less than 0.025 eV, a relative reaction rate constant κ−/κ0 falls below one. The reason for this phenomenon is that, one hand, a relative reaction rate constant κ−/κ0 monotonically increases as a coupling strength ΩR/ω0 increases due to absence of a pre-exponent term (a term added in front of an exponential function) in Equation 17 being Arrhenius-type, on the other hand, a pre-exponent term (1−½·ΩR/ω0) suppresses increase of a relative reaction rate constant κ−/κ0 in Equation 18 being Eyring-type. However, considering that a deep strong coupling has not been realized and therefore does not need to be considered under the present conditions, and a discrepancy between Equations 17 and 18 is relatively small and therefore the two draw nearly identical curves in the weak coupling, strong coupling, and ultra strong coupling regions, whether to use Equation 17 or 18 makes no big difference in evaluation of promotion of a chemical reaction by a vibrational coupling.
Furthermore, results of quantitatively evaluating an effect of a vibrational coupling on a chemical reaction, based on Equations 17 and 18, under a wide range of parameter conditions, that is, activation energy Ea0 in a range of 0.005 to 2.000 eV, a coupling strength ΩR/ω0 in a range of 0.0005 to 2.000, and temperature T in a range of 10 to 1000 K, will be discussed in detail in [Example 1] to [Example 3]. Examples 1 to 3 provide findings covering nearly every chemical reaction condition and vibrational coupling condition with regard to promotion of a chemical reaction by a vibrational coupling.
[(2) Process of Materializing Structure Satisfying Requirement Necessary for Vibrational Coupling]
Next, with regard to Item (2), a process of materializing a structure satisfying a requirement necessary for a vibrational coupling will be discussed based on Item (1), according to Items (2)-A, (2)-B, and (2)-C described below. Specific productions of the structure will be discussed later in the Description of Production Method section.
(2)-A: an opto-electrical field confinement structure for forming an optical mode and a requirement of the structure
(2)-B: a vibrational mode possessed by a chemical material used in a chemical reaction and a requirement of the vibrational mode
(2)-C: a vibrational coupling between an optical mode and a vibrational mode, and a requirement of the vibrational coupling
[(2)-A: Opto-Electrical Field Confinement Structure for Forming Optical Mode and Requirement of Structure]
With regard to item (2)-A, an opto-electrical field confinement structure for forming an optical mode and a requirement of the structure will be discussed. The first structure to be listed as a structure capable of confining an opto-electrical field is a Fabry-Pérot cavity. As illustrated in (A) in
where km denotes a wavenumber (unit: cm−1) of the m-th optical mode, and m denotes an optical mode number and is a natural number. For example, when a cavity length t is nearly equal to an infrared wavelength, that is, t=1 to 100 μm, an optical mode of the Fabry-Pérot cavity 7 can be measured by a Fourier transform infrared spectrophotometer (FT-IR) or the like. (B) in
In the m-th optical mode, a ratio between a half-value width Δkm and a wavenumber of the optical mode km is referred to as a quality factor (Q factor) and is defined by Equation 22 below.
A Q factor is one of performance indices of an opto-electrical field confinement structure and the reciprocal thereof is proportional to a decay of the m-th optical mode. Accordingly, as a Q factor increases, a confinement time of an opto-electrical field becomes longer, and performance as a cavity becomes better. Further, since a Q factor and a coupling strength: ΩR/ω0 are in a proportional relation, referring to Equation 17 or 18, as a Q factor takes a larger value, a relative reaction rate constant κ−/κ0 increases. However, based on experimental results, a Q factor with magnitude of at most 20 can provide a practical effect on promotion of a chemical reaction by a vibrational coupling. A mode volume can be cited as another performance index of a cavity. As indicated in Equation 1, Rabi splitting energy hΩR is inversely proportional to the square root of a mode volume V. Accordingly, in order to increase a coupling strength ΩR/ω0 for a purpose of increasing a relative reaction rate constant κ−/κ0, the smaller the mode volume V, the more favorable. However, while the mode volume V depends on a cavity length t defining a wavenumber of an optical mode km with regard to the Fabry-Pérot cavity 7, the wavenumber of an optical mode km needs to match a wavenumber of the vibrational mode with regard to a vibrational coupling. As such, when the Fabry-Pérot cavity 7 is used for a vibrational coupling, a mode volume V is naturally determined to be a certain value and therefore is handled as an invariant instead of an adjustable variable.
In addition, a surface plasmon-polariton structure can be cited as another structure capable of confining an electric field of light. In general, a surface plasmon-polariton structure refers to a structure on which many materials, typically metal, with a dielectric function the real part of which is negative and has a large absolute value, and the imaginary part of which has a small absolute value, are cyclically arranged on a dielectric surface as a microstructure with a size and a pitch both around a wavelength of target light. When the metal microstructure is used for vibrational coupling, a size and a pitch of the structure is around a wavelength of infrared light, that is, 1 to 100 μm.
Next, propagation and decay of an optical mode will be discussed. An interface between a dielectric (a dotted part) and metal (a shaded part) to is considered as illustrated in (A) in
where λ denotes a wavelength (λ=2πc/ω, where c: speed of light) and Im(C) denotes an operator for taking the imaginary part of a complex number C. In general, a dielectric constant of a material is a complex dielectric function including an imaginary part and a real part, and the complex dielectric function is wavelength-dependent. Accordingly, the decay length Lz and the propagating length Lx have wavelength dependence. Referring to (B) in
First, taking a close look at wavenumber (wavelength) dependence of the decay length L in (a) illustrated in (B) in
Classifying the metals suited to the purpose of chemical reaction promotion by a vibrational coupling, based on the aforementioned three characteristics related to wavenumber (wavelength) dependence of the decay length Lz silver and gold are most excellent, then aluminum, copper, tungsten are desirable, and nickel, platinum, cobalt, iron, palladium, and titanium are fair. Another material may be used as long as the real part of a dielectric function of the material is negative and has a large absolute value, and the imaginary part of the dielectric function has a small absolute value; and single-element metal, an alloy, metallic oxide, graphene, graphite, or the like that are not taken up here are also applicable.
Next, referring to a propagating length Lz in (13) illustrated in (B) in
Classifying the metals in terms of suitability for the purpose of chemical reaction promotion by a vibrational coupling, based on the aforementioned three characteristics related to wavenumber (wavelength) dependence of a propagating length Lx, silver, gold, aluminum, copper, tungsten, nickel, platinum, cobalt, iron, palladium, and titanium can be listed in descending order of suitability. Another material may be used as long as the real part of a dielectric function of the material is negative and has a large absolute value, and the imaginary part of the dielectric function has a small absolute value; and single-element metal, an alloy, metallic oxide, grapheme, graphite, or the like that are not taken up here are also applicable.
[(2)-B: Vibrational Mode Possessed by Chemical Material Used in Chemical Reaction and Requirement of Vibrational Mode]
With regard to Item (2)-B, a vibrational mode possessed by a chemical material used in a chemical reaction and a requirement of the vibrational mode will be discussed. A molecule composed of N atoms has 3N−6 vibrational modes excluding degrees of freedom of translation and rotation (3N−5 for a linear molecule). Among such vibrational modes, a vibrational mode usable for a vibrational coupling is limited to dipole allowance. The reason is that, as indicated in Equation 1, when a transition dipole moment d is zero, Rabi splitting energy hΩR becomes zero, and consequently, a coupling strength ΩR/ω0 also becomes zero. Actually, substituting ΩR/ω0=0 into Equation 17 or 18 yields κ−/κ0=1, therefore chemical reaction promotion by a vibrational coupling is not provided. Dipole allowance refers to infrared activity, meaning that there is a certain infrared absorption in a molecule. An infrared-active vibrational mode includes anti-symmetric stretching vibration, anti-symmetric deformation vibration, or the like when the molecule has a center of symmetry, whereas, in the absence of a center of symmetry, symmetric stretching vibration, symmetric deformation vibration, or the like are also included in addition to the anti-symmetric stretching vibration, the anti-symmetric deformation vibration, or the like. According to Equation 1, Rabi splitting energy hΩR is proportional to a transition dipole moment d. In other words, as a transition dipole moment d increases, a coupling strength ΩR/ω0 increases, and a relative reaction rate constant κ−/κ0 also increases, based on Equation 17 or 18. Namely, a vibrational coupling promotes a chemical reaction more rapidly when a vibrational mode has a larger transition dipole moment d.
Table 1 lists literature values or experimental values of transition dipole moments d of various vibrational modes. The unit of a transition dipole moment d is expressed by debye (D, where 1 D=3.336×10−3° Referring to Table 1, a general tendency is that a transition dipole moment d has a relatively larger value in a vibrational mode between different atoms rather than between the same atoms, in a vibrational mode between atoms with a small mass difference rather than between atoms with a large difference, a vibrational mode with a multiple bond rather than a single bond, and a vibrational mode with a long conjugated system rather than a short conjugated system. This tendency is also inherited to a degree of promotion of a chemical reaction by a vibrational coupling. In other words, a chemical material including a vibrational mode of a multiple bond between atoms with a relatively small mass difference, such as a vibrational mode of each of C═N, C═O, C═P, C═S, N═O, N═P, N═S, and O═S is expected to further enjoy an effect of chemical reaction promotion by a vibrational coupling.
On one hand, a transition dipole moment d is vibrational mode inherent, that is, chemical material inherent, and therefore cannot be changed once a reaction system is determined. On the other hand, according to a theory indicated by Equation 1, Rabi splitting energy hΩR is proportional to the square root of a concentration of a matter C (C=N/V, where N is a number of a matter and V is a mode volume and further according to an experiment discussed in [Example 5], the Rabi splitting energy hΩR is proportional to the 0.4-th power of the concentration of the matter C. That is, theoretically ΩR ∝C0.5 holds, and experimentally ΩR ∝C0.4 holds. Consequently, in either case, as a means of raising a degree of promotion of a chemical reaction by a vibrational coupling, increasing a relative reaction rate constant κ−/κ0 by increasing a coupling strength ΩR/ω0 through increasing a concentration C is a versatile method. By use of Equation 17, an effect of magnitude of a concentration C on a relative reaction rate constant KJK0 can be quantitatively estimated. While the concentration dependence of a relative reaction rate constant κ−/κ0 will be discussed in detail in [Example 6], the conclusion is as follows: raising a concentration of a chemical material is effective as a means of increasing a reaction rate constant under a vibrational coupling unless a coupling strength enters the deep strong coupling region expressed by Equation 5. In particular, a concentration increase brings about a remarkable effect to a vibrational strong coupling and a vibrational ultra strong coupling.
[(2)-C: Vibrational Coupling Between Optical Mode and Vibrational Mode, and Requirement of Vibrational Coupling]
With regard to Item (2)-C, a vibrational coupling between an optical mode and a vibrational mode, and a requirement of the vibrational coupling will be discussed. A condition for achieving a vibrational coupling by use of the Fabry-Pérot cavity 7 is expressed by Equation 25 below using a wavenumber of an optical mode km and a wavenumber of a vibrational mode ω0.
[Math. 34]
ω0=km=mk0(m=1, 2, 3, . . . ) (Equation 25)
where k0 denotes a free spectral range, as discussed above. As defined in Item (1)-A, ω0 denotes an angular frequency (unit: s−1); however, since a physical quantity acquired by an experiment is a wavenumber (unit: cm−1), ω0 is hereinafter referred to as a wavenumber. In addition, since (energy)=(Planck constant)×(frequency)=(Dirac constant)×(angular frequency)=(Planck constant)×(speed of light)×(wavenumber) holds, energy, a frequency, an angular frequency, and a wavenumber are interchangeable.
As illustrated in (A) in
In Equation 25, ω0 denotes a wavenumber of a vibrational mode of a chemical bond constituting a reactant material in a desired chemical reaction. In other words, a wavenumber of a vibrational mode in an original system ω0 is a constant value inherent to a chemical material in the original system, and therefore there is no degree of freedom for adjustment. Thus, when a vibrational coupling is used for promotion of a chemical reaction, a wavenumber of an optical mode km is to be adjusted to match a wavenumber of a vibrational mode ω0. As discussed in Item (2)-A, an optical mode is composed of the first optical mode, the second optical mode, the third optical mode, . . . , the m-th optical mode, and therefore there are in choices, which satisfy to the condition in Equation 25. An optical mode best suited for chemical reaction promotion by a vibrational coupling is not obvious. As illustrated in aforementioned (A) to (D) in
[(3) Process of Materializing Vibrational Coupling Chemical Reaction Device and Producing and Processing Desired Chemical Material]
Finally, with regard to Item (3), a process of materializing a vibrational coupling chemical reaction device in which a purpose of performing a vibrational coupling is compatible with a purpose of performing a chemical reaction, and producing and processing a desired chemical material by use of the device will be discussed on the basis of Item (2), according to Items (3)-A, (3)-B, and (3)-C described below:
(3)-A: Capacity increase of a vibrational coupling chemical reaction device by a linear cavity,
(3)-B: Mode number increase in a vibrational coupling chemical reaction device by a linear cavity, and
(3)-C: Modularization, unitization, and systematization of a vibrational coupling chemical reaction device.
[(3)-A: Capacity increase of Vibrational Coupling Chemical Reaction Device by Linear Cavity]
First, with regard to item (3)-A, a concept of a linear cavity and capacity increase of a vibrational coupling chemical reaction device by a linear cavity will be discussed. One hand, the Fabry-Pérot cavity 7 in
Referring to
(B) in
[(3)-B: Mode Number Increase in Vibrational Coupling Chemical Reaction Device by Linear Cavity]
Next, with regard to Item (3)-B, mode number increase in a vibrational coupling chemical reaction device by a linear cavity will be discussed. A number of configurable optical modes in a linear cavity depends on a cross-sectional shape of the cavity. In other words, a linear cavity makes it possible to multiply a number of vibrationally coupled vibrational modes, thereby enabling a multimode operation for a vibrational coupling. A specific example is shown in
(A) in
(B) in
(C) in
In general, when a cross-sectional shape is a parallelo-2p-sided polygon (where p is an integer greater than or equal to 2), a number of spatially independent optical modes is p, and therefore, for example, a number of spatially independent optical modes is two in the parallelogrammatical linear cavity 20, three in the parallelo-hexagonal linear cavity 21, four in the parallelo-octagonal linear cavity 22, and theoretically infinite in the elliptical linear cavity 23, assuming that a number of sides is infinite. When a cross-sectional shape is a regular 2p-sided polygon, and all p sets of parallel sides have the same length, a number of spatially independent optical modes is p; however, because all modes degenerate energetically and have the same frequency, practically, there is only one optical mode in the cavity. Accordingly, a regular 2p-sided polygonal linear cavity can vibrationally couple with only one vibrational mode possessed by a chemical material. Further, when a cross-sectional shape is an inequilateral parallelo-2p-sided polygon and all p sets of parallel sides have different lengths, there are p spatially and energetically independent optical modes in the cavity. Thus, an inequilateral parallelo-2p-sided polygonal linear cavity can vibrationally couple simultaneously with p different vibrational modes possessed by a chemical material. Furthermore, when a cross-sectional shape is a general 2p-sided polygon and lengths of p sets of parallel sides can be classified into q, a number of spatially independent optical modes is p, whereas a number of energetically different optical modes is q. As a result, a general 2p-sided-polygonal linear cavity can vibrationally couple simultaneously with q different vibrational modes possessed by a chemical material.
As discussed above, by defining a cross-sectional shape of a linear cavity, the linear cavity can vibrationally couple with a single to a multiple of vibrational modes possessed by a chemical material, that is, can realize a multi-mode operation, thereby enabling to handle diverse chemical reactions. In particular, when a chemical reaction proceeds with a multiple raw materials, a linear cavity can simultaneously activate vibrational modes related to a chemical reaction in each raw material, thereby exhibiting outstanding performance in synergistically accelerating a reaction rate of the entire chemical reaction.
[(3)-C: Modularization, Unitization, and Systematization of Vibrational Coupling Chemical Reaction Device]
Finally, with regard to Item (3)-C, modularization, unitization, and systematization of a vibrational coupling chemical reaction device will be discussed.
The reason why the example embodiment of the present invention can provide modularization of a chemical reaction device is derived from the following two facts: first, the principle of chemical reaction promotion does not require preparation of a specific elementary composition and surface state for each chemical reaction as is the case with a normal catalytic action. Second, it is only necessary to prepare an optical mode, which is determined solely by a structure and is coupled specifically with a vibrational mode related to a chemical reaction. Thus, according to the example embodiment of the present invention, because a frequency of an optical mode is determined solely by a cavity length, it is very easy to standardize module products. For example, referring to
In addition to an advantage of being capable of capacity increase by accumulation described in the previous item, the vibrational coupling chemical reaction device module 36 illustrated in
(A) in
(B) in
(C) in
(D) in
(E) in
(F) in
As described above, modularization, unitization, and systematization according to the example embodiment of the present invention can handle diverse production/processing scales ranging from small-scale fewer-item production to mass production and enables easy recombination, rearrangement, and exchange as needed, and therefore is useful in greatly reducing production/processing costs and greatly improving productivity.
Production of a chemical material by use of a vibrational coupling chemical reaction device will be discussed in detail in [Example 8] to [Example 11].
As described above, the vibrational coupling chemical reaction device according to the example embodiment of the present invention can decrease vibrational energy and reduce activation energy of a chemical reaction, by vibrationally coupling an optical mode formed by an opto-electrical field confinement structure with a vibrational mode of a chemical material related to the chemical reaction, and therefore can promote the chemical reaction. Thus, the vibrational coupling chemical reaction device according to the example embodiment of the present invention includes a catalytic action; however, while a normal catalyst depends on a chemical property of a component, the vibrational coupling chemical reaction device according to the example embodiment of the present invention is component independent and depends solely on a structural parameter of an opto-electrical field confinement structure. Accordingly, every type of chemical reaction can be accelerated merely by adjusting the structural parameter. Further, when a coupling strength ΩR/ω0 being an indicator of a vibrational coupling is in the ultra strong coupling region, the vibrational coupling chemical reaction device according to the example embodiment of the present invention can perform a chemical reaction requiring a reaction temperature of 1000° C. at room temperature. In addition, the vibrational coupling chemical reaction device according to the example embodiment of the present invention can further promote a chemical reaction as activation energy of a chemical reaction increases. For example, on condition of ΩR/ω0=1, the vibrational coupling chemical reaction device according to the example embodiment of the present invention can tremendously accelerate a reaction rate by a million times when activation energy is 0.5 eV and by a trillion times when activation energy is 1.0 eV. Furthermore, a normal catalyst cannot exert a catalytic action unless the catalyst and a raw material get close to one another down to the subnanometer order in such a way as to contact through chemisorption or physisorption, whereas the vibrational coupling chemical reaction device according to the example embodiment of the present invention can exert a catalytic action on a raw material, once the raw material enters a range of the submillimeter order where an optical mode can exist. Specifically, the vibrational coupling chemical reaction device according to the example embodiment of the present invention can maintain the catalytic effect up to a million times the distance of a normal catalyst. Moreover, according to the example embodiment of the present invention, efficient production and processing of a chemical material accommodating diverse scales ranging from small-scale fewer-item production to mass production/processing can be achieved by modularizing, unitizing, and systematizing the vibrational coupling chemical reaction device, and easy recombination, rearrangement, and exchange can be performed as needed, all of which are useful for greatly reducing production/processing costs and greatly improving productivity.
A production method according to the example embodiment will be discussed with reference to
(A) in
(B) in
(C) in
(D) in
(E) in
(A) in
(B) in
(C) in
(D) in
(E) in
(F) in
(G) in
As illustrated in (c) in (B) in
Examples of the present invention are listed below. [Example 1] to [Example 3] are related to Item (1) described above and describe results of quantitative evaluations of an effect of vibrational coupling on a chemical reaction under a wide range of chemical reaction conditions, based on Equation 17 or 18 being an equation expressing a relative reaction rate constant κ−/κ0 under a vibrational coupling.
From a glance at (A) to (I) in
Finally, as a supplement to
The above findings gained from
Viewing (A) in
The above findings acquired from
An overall tendency in (A) to (I) in
The above findings obtained from
[Example 4] to [Example 6] are related to Item (2) described above and describe production of a vibrational coupling chemical reaction device and results of basic performance evaluations of the device. Then, basic characteristics of a vibrational coupling required for production of a desired chemical material by the vibrational coupling chemical reaction device, that is, concentration dependence of a coupling strength, relative concentration dependence of a relative reaction rate constant under a vibrational coupling, optical mode number dependence of Rabi splitting energy, and the like will be discussed with a particular emphasis on results acquired by experiments using the vibrational coupling chemical reaction device.
A vibrational coupling chemical reaction device was produced by the means discussed in Description of Production Method. A brief description is as follows. Zinc selenide (ZnSe) being transparent in an infrared region was employed as a substrate in such a way that a finished product of the vibrational coupling chemical reaction device can be evaluated by a Fourier-transform infrared absorption spectroscopy (FT-IR) device. Two ZnSe substrates were prepared, and both were optically polished and washed by a proper method, and subsequently, gold was sputter-deposited in a vacuum with a thickness of 10 nm. Then, in order to prevent the gold thin film from contacting a chemical material, a 100 nm SiO2 layer was formed on each of the two gold/ZnSe substrates. As the formation method of the SiO2 protective film, a method of first applying a 5% xylene solution of perhydropolysilazane [(—SiH2—NH—)n] to the gold/ZnSe substrates, drying by 100° C. heating, then promoting a chemical reaction of (—SiH2—NH—)n+2nH2O→(SiO2)n+nNH3+2nH2 by ultraviolet irradiation, and finally, completing transformation into quartz (transformation into SiO2) by 250° C. heating was used. Finally, a Fabry Pérot cavity was formed by laying the two SiO2/gold/ZnSe substrates on top of another, sandwiching a spacer made of plastic resin such as Teflon or Mylar. The completed Fabry-Pérot cavity, was housed in a holder including a mechanism capable of applying uniform pressure on the two SiO2/gold/ZnSe substrates, and then a vibrational coupling chemical reaction device was completed. A cavity length was roughly defined by a thickness of the spacer, and fine adjustment was performed by the loading mechanism in the holder.
(A) in
The reason for increase in a difference between transmission and absorption of light is that an opto-electrical field confinement effect increases on the higher wavenumber side, and this is a property inherent to a Fabry-Pérot cavity.
Table 2 lists optical characteristics related to the vibrational coupling chemical reaction device as a Fabry-Pérot cavity. Referring to Table 2, a free spectral range k0 is nearly constant between respective optical modes and an average value thereof is 391.82 cm−1. By substituting the value and the refractive index of air being 1 into Equation 21, a cavity length t becomes 12.76 μm. The thickness of the spacer used was 10 μm, and therefore t=12.76 μm is somewhat longer than the spacer thickness. When a loading mechanism of a holder was used in a separate experiment, the cavity length t was variable in a range of (spacer thickness+3.5 μm±2.5 μm, and fine adjustment could be performed on a target wavenumber at ±1 cm−1 accuracy. Further, a Q factor gradually increased from Q=57.22 at the second optical mode, took a maximum value, Q=125.9, at the sixteenth optical mode, and then, gradually decreased; and an average value was 103.0. Since the value greatly exceeds a Q factor required for vibrational coupling being Q=20, the vibrational coupling chemical reaction device exhibits a sufficient capability of opto-electrical field confinement. Next, a performance test was done with the vibrational coupling chemical reaction device filled with a chemical material. The result will be discussed below.
(B) to (D) in
In the case of (b) in (B) in
In the case of (b) in (C) in
In the case of (b) in (D) in
On the basis of the results discussed above, the vibrational coupling chemical reaction device in the examples of the present invention has been demonstrated to possess a function as a cavity with a precision level for adjusting a resonance condition required for a vibrational coupling with an accuracy of ±1 cm−1, together with not only optical rigidity which lasts a minimum of 8 hours, but also a function as a chemical reaction container keeping a volatile chemical material air-tightly for a minimum of 8 hours.
In this example, examination results of concentration dependence of a coupling strength ΩR/ω0 by use of the vibrational coupling chemical reaction device acquired in [Example 4] will be discussed.
(A) in
As discussed above, it has been clarified as a basic finding useful in producing a desired chemical material by the vibrational coupling chemical reaction device that, while concentration dependence of a coupling strength is theoretically expressed as ΩR/ω0 ∝C0.5, the dependence is experimentally expressed as ΩR/ω0∝C0.4.
In this example, results of analyzing concentration dependence of a relative reaction rate constant κ−/κ0, based on Equation 17, will be discussed.
In this example, examination results of optical mode dependence of a coupling strength ΩR/ω0 by use of the vibrational coupling chemical reaction device acquired in [Example 4] will be discussed.
(A) in
[Example 8] to [Example 11] are related to item (3) described above and describe results of actually producing a desired material by use of the vibrational coupling chemical reaction promotion device produced in [Example 4], on the basis of a chemical reaction under a vibrational coupling quantified in [Example 1] to [Example 3].
In this example, an experimental result proving that a product I [see (A) in
Experimental conditions are as follows.
Every experiment was performed at room temperature (T=300 K) and (triphenylphosphoranylidene) ketene was metered to be an acetone solution with a concentration of 0.250 M. An acetone concentration was 13.6 M and is overly excessive against (triphenylphosphoranylidene) ketene. For the absence of a vibrational coupling, an experiment was performed in a non-resonant condition by use of a chemical reaction device without mirror planes produced by the means described in Description of Production Method. For the presence of a vibrational strong coupling, a chemical reaction device with mirror planes produced by the means described in Description of Production Method was used, and an optical mode was coupled with a vibrational mode by strictly adjusting a cavity length. Two kinds of vibrational couplings, a C═O resonance and an S═C═S resonance, were examined. For the vibrational coupling of the C═O resonance, when the sixth optical mode (k6=6k0=1712 cm−1) of a cavity with a cavity, length of t=12.38 μm was resonantly coupled with a C═O stretching vibrational mode (vibrational quantum number 0→1 transition: 1712 cm−1) of acetone, the coupling strength was ΩR/ω0=0.0644 and the Q factor was Q=13.37. For the vibrational coupling of the C═C═O resonance, when the seventh optical mode (k7=7k0=2100 cm−1) of a cavity with a cavity length of t=11.58 pin was resonantly coupled with a C═C═O anti-symmetric stretching vibrational mode (vibrational quantum number 0→1 transition: 2100 cm−1) of (triphenylphosphoranylidene) ketene, the coupling strength was ΩR/ω0=0.0614 and the Q factor was Q=13.79. Both vibrational couplings belong to the strong coupling (0.01≤ΩR/ω0<0.1) expressed by Equation 3. Since activation energy of the chemical reaction in (A) in
In order to determine a reaction rate constant, infrared absorption spectra were measured at regular time intervals with an FT-IR instrument. For the absence of a vibrational coupling, a temporal change in concentration was directly determined from a temporal change in absorbance for the C═C═O infrared absorption band of (triphenylphosphoranylidene) ketene. Meanwhile, for the presence of a vibrational coupling, an absorbance of an infrared absorption band of (triphenylphosphoranylidene) ketene was extracted by performing waveform separation on the measured infrared spectrum consisting optical and vibrational modes using a suitable spectral function such as the Lorentz function or the inverse Lorentz function, and then the extracted temporal change in absorbance was used for determining a temporal change in concentration. When estimating a reaction rate constant, a reaction profile was analyzed by fitting to the zeroth-order rate equation, C=κt+C0, where t: concentration, C0: initial concentration, κ: reaction rate constant, and t: time. A reaction rate constant in the vibrational coupling of the C═O resonance is denoted as κ−(C═O) and a reaction rate constant in the vibrational coupling of the C═C═O resonance is denoted as κ−(C═c═O), and respective ratios to a reaction rate constant κ0 without a vibrational coupling were derived as relative reaction rates κ−(C═O)/κ0 and κ−(C═C═O)/κ0.
Experimental results are as follows.
(B) in
(C) in
It is thus proven from the experimental results described above that a purpose of opto-electrical field confinement is compatible with a purpose of performing a chemical reaction in a chemical reaction device produced by the method described in Description of Production Method, a vibrational coupling promotes a chemical reaction as predicted by use of Equation 1.7 or 18, and the chemical reaction device produced by the method described in Description of Production Method can actually produce a target chemical material.
In this example, experimental results proving that methyl N-phenylcarbamate (Ph-NH—CO—O—CH3) being a target material can be produced with an accelerated reaction rate by using a vibrational coupling to chemical reaction device produced by the means described in Description of Production Method, with respect to a chemical reaction with phenyl isocyanate (PhN═C═O) and methanol (CH3OH) as raw materials, the chemical reaction being illustrated in (A) in
Experimental conditions are as follows.
Every experiment was performed at room temperature (T=300 K), and each of phenyl isocyanate and methanol was metered to be a chloroform solution with a concentration of 1.00 M. For the absence of a vibrational coupling, an experiment was performed in a non-resonant condition by use of a chemical reaction device without mirror planes produced by the means described in Description of Production Method. For the presence of a vibrational strong coupling, a chemical reaction device with mirror planes produced by the means described in Description of Production Method was used, and an optical mode was coupled with a vibrational mode by strictly adjusting a cavity length. A vibrational coupling of a C═C═O resonance was examined. Specifically, when the ninth optical mode (k9=9k0=2:272 cm−1) of a cavity with a cavity length of t=13.76 μm was resonantly coupled with an N═C═O anti-symmetric stretching vibrational mode (vibrational quantum number 0→1 transition: 2272 cm−1) of phenyl isocyanate, the coupling strength was ΩR/ω0=0.0452 and the Q factor was Q=33.91. The vibrational coupling belongs to the strong coupling (0.01≤ΩR/ω0<0.1) expressed by Equation 3. Since activation energy of the reaction in (A) in
In order to determine a reaction rate constant, infrared absorption spectra were measured at regular time intervals with an FT-1R instrument. For the absence of a vibrational coupling, a temporal change in concentration was directly determined from a temporal change in absorbance for the N═C═O infrared absorption band of phenyl isocyanate. Meanwhile, for the presence of a vibrational coupling, an absorbance of an infrared absorption band of phenyl isocyanate was extracted by performing waveform separation on the measured infrared spectrum consisting optical and vibrational modes using a suitable spectral function such as the Lorentz function or the inverse Lorentz function, and then the extracted temporal change in absorbance was used for determining a temporal change in concentration. When estimating a reaction rate constant, a bimolecular reaction was assumed, and a reaction profile was analyzed by fitting to the second-order rate equation C−1=κt±C0−1, where C: concentration, C0: initial concentration, κ: reaction rate constant, and t: time. A reaction rate constant in the vibrational coupling of the N═C═O resonance is denoted as κ−(C═C═O) and a ratio κ−(N═C═O)/κ0 to the reaction rate constant κ0 in the case of without a vibrational coupling was derived as a relative reaction rate.
Experimental results are as follows.
(B) in
It is thus proven from the experimental results described above that the purpose of opto-electrical field confinement is compatible with the purpose of performing a chemical reaction n a chemical reaction device produced by the method described in [Description of Production Method], a vibrational coupling promotes a chemical reaction as predicted by use of Equation 17 or 18, and the chemical reaction device produced by the method described in Description of Production Method can actually produce a target chemical material.
In this example, experimental results proving that (triphenylphosphoranylidene) thioketene (Ph3P═C═C═S) and carbonyl sulfide (S═C═O) being target materials can be produced with an accelerated reaction rate by using a vibrational coupling chemical reaction device produced by the means described in Description of Production Method, with respect to a chemical reaction with.
(triphenylphosphoranylidene) ketene (Ph3P═C═C═ and carbon disulfide (CS2) as raw materials, the chemical reaction being illustrated in (A) in
Experimental conditions are as follows.
Every experiment was performed at room temperature (T=300 K), and each of (triphenylphosphoranylidene) ketene and carbon disulfide was metered to be a chloroform solution with a concentration of 1.00 M. For the absence of a vibrational coupling, an experiment was performed in a non-resonant condition by use of a chemical reaction device without mirror planes produced by the means described in Description of Production Method. For the presence of a vibrational strong coupling, a chemical reaction device with mirror planes produced by the means described in Description of Production Method was used, and an optical mode was coupled with a vibrational mode by strictly adjusting a cavity length. Two kinds of vibrational couplings, a C═C═O resonance and an S═C═S resonance, were examined. For the presence of the vibrational coupling of the C═C═O resonance, when the ninth optical mode (k9=9k0=2100 cm−1) of a cavity with a cavity length of t=14.85 μm was resonantly coupled with a C═C═O anti-symmetric stretching vibrational mode (vibrational quantum number 0→1 transition: 2100 cm−1) of (triphenylphosphoranylidene) ketene, the coupling strength was ΩR/ω0=0.0535 and the Q factor was Q 26.92. For the presence of the vibrational coupling of the S═C═S resonance, when the sixth optical mode (k6=6k0=1519 cm1) of a cavity with a cavity length of t=13.72 μm was resonantly coupled with an S═C═S anti-symmetric stretching vibrational mode (vibrational quantum number 0→1 transition: 1519 cm−1) of carbon disulfide, the coupling strength was ΩR/ω0=0.0359 and the Q factor was Q=29.67. Both vibrational couplings belong to the strong coupling (0.01≤ΩR/ω0<0.1) expressed by Equation 3. Since activation energy of the reaction in (A) in
In order to determine a reaction rate constant, infrared absorption spectra were measured at regular time intervals by use of an FT-1R instrument. For the absence of a vibrational coupling, a temporal change in concentration was directly determined from a temporal change in absorbance for the C═C═O infrared absorption band of (triphenylphosphoranylidene) ketene. Meanwhile, for the presence of a vibrational coupling, an absorbance of an infrared absorption band of (triphenylphosphoranylidene) ketene was extracted by performing waveform separation on the measured infrared spectrum consisting optical and vibrational modes using a suitable spectral function such as the Lorentz function and the inverse Lorentz function, and then the extracted temporal change in absorbance was used for determining a temporal change in concentration. When estimating a reaction rate constant, a unimolecular reaction was assumed, and a reaction profile was analyzed by fitting to the first-order rate equation ln C=−κ1+ In C0, where C: concentration, C0: initial concentration, κ: reaction rate constant, and t: time. A reaction rate constant in the vibrational coupling of the C═C═O resonance is denoted as κ−(C═C═O) and a reaction rate constant in the vibrational coupling of the S═C═S resonance is denoted as κ−(S═C═s), and respective ratios to a reaction rate constant κ0 in the case of without a vibrational coupling were derived as relative reaction rates κ−(C═C═O)/κ0 and κ−(S═C═X)/κ0.
Experimental result are as follows.
(B) in
(C) in
It is thus proven from the experimental results described above that the purpose of opto-electrical field confinement is compatible, with the purpose of performing a chemical reaction in a chemical reaction device produced by the method described in [Description of Production Method], a vibrational coupling promotes a chemical reaction as predicted by use of Equation 17 or 18, and the chemical reaction device produced by the method described in Description of Production Method can actually produce a target chemical material.
In this example, experimental results proving that (triphenylphosphoranylidene) methyl acetate (Ph3P═CH—CO—O—CH3) being a target material can be produced with an accelerated reaction rate by using a vibrational coupling chemical reaction device produced by the means described in Description of Production Method, with respect to a chemical reaction with (triphenylphosphoranylidene) ketene (Ph3P═C═C═O) and methanol (CH3OH) as raw materials, the chemical reaction being illustrated in (A) in
Experimental conditions are as follows.
Every experiment was performed at room temperature (t=300 K), and each of (triphenylphosphoranylidene) ketene and methanol was metered to be a 1,2-dichloroetharte solution with a concentration of 0.500 M. For the absence of a vibrational coupling, an experiment was performed in a non-resonant condition by use of a chemical reaction device without mirror planes produced by the means described in Description of Production Method. For the presence of a vibrational strong coupling, a chemical reaction device with mirror planes produced by the means described in Description of Production Method was used, and an optical mode was coupled with a vibrational mode by strictly adjusting a cavity length. A vibrational coupling of a C═C═O resonance was examined. Specifically, when the ninth optical mode (k9=9k0=2100 cm−1) of a cavity with a cavity length of T=14.95 μm was resonantly coupled with a C═C═O anti-symmetric stretching vibrational mode (vibrational quantum number 0→1 transition: 2100 cm−1) of (triphertylphosphoranylidene) ketene, the coupling strength was ΩR/ω0=0.0718. The vibrational coupling belong to the strong coupling (0.01≤ΩR/ω0<0.1) expressed by Equation 3. Since activation energy of the reaction in (A) in
In order to determine a reaction rate constant, infrared absorption spectra were measured at regular time intervals by use of an FT-IR instrument. For the absence of a vibrational coupling, a temporal change in concentration was directly determined from a temporal change in absorbance for the C═C═O infrared absorption band of (triphenylphosphoranylidene) ketene. Meanwhile, for the presence of a vibrational coupling, an absorbance of an infrared absorption band of (triphenylphosphoranylidene) ketene was extracted by performing waveform separation on the measured infrared spectrum consisting optical and vibrational modes using a suitable spectral function such as the Lorentz function or the inverse Lorentz function, and then the extracted temporal change in absorbance was used for determining a temporal change in concentration. When estimating a reaction rate constant, a bimolecular reaction was assumed, and a reaction profile was analyzed by fitting to a second-order rate equation C−1=κtT C0−1 where C: concentration, C0: initial concentration, κ: reaction rate constant, and t: time. A reaction rate constant in the vibrational coupling of the C═C═O resonance is denoted as κ−(C═C═O), and a ratio κ−(C═C═O/κ0 to the reaction rate constant κ0 in the case of without a vibrational coupling was derived as a relative reaction rate.
Experimental result are as follows.
(B)
(C) in
It is thus proven from the experimental results described above that the purpose of opto-electrical field confinement is compatible with the purpose of performing a chemical reaction in a vibrational coupling chemical reaction device produced by the method described in [Description of Production Method], a vibrational coupling promotes a chemical reaction as predicted by use of Equation 17 or 18, and the vibrational coupling chemical reaction device produced by the method described in [Description of Production Method] can actually produce a target chemical material.
While the preferred example embodiments and exam es of the present invention have been described above, the present invention is not limited thereto. It goes without saying that various modifications may be made within the scope of the invention described in the claims and such modifications are also included in the scope of the present invention.
The example embodiments and the examples described above may also be described in part or in whole as the following supplementary notes but are not limited thereto.
(Supplementary Note 1) A chemical reaction device including an opto-electrical field confinement chemical reaction container structure integrating an opto-electrical field confinement structure forming an optical mode having a frequency identical to or close to a vibrational nmode of a chemical material related to a chemical reaction with a chemical reaction container structure including a space for storing fluid required for the chemical reaction including the chemical material, wherein
a chemical reaction is promoted by vibrationally coupling the optical mode with the vibrational mode.
(Supplementary Note 2) The chemical reaction device according to Supplementary Note 1, wherein
an amount of activation energy of the chemical reaction is reduced by vibrationally coupling the optical mode with the vibrational mode.
(Supplementary Note 3) The chemical reaction device according to Supplementary Note 1 or 2, wherein
the chemical reaction container structure includes an inlet and an outlet of the fluid.
(Supplementary Note 4) The chemical reaction device according to any one of Supplementary Notes 1 to 3, wherein
the chemical reaction device is connected to one or more other chemical reaction devices through the inlet and the outlet.
(Supplementary Note 5) The chemical reaction device according to any
one of Supplementary Notes 1 to 4, wherein the opto-electrical field confinement structure is a Fabry-Pérot cavity including two mirror planes parallel to each other.
(Supplementary Note 6) The chemical reaction device according to Supplementary Note 5, wherein
the Fabry-Pérot cavity is a linear cavity including a structure with a sufficiently long prismatic shape having one or more sets of two mirror planes parallel to each other as sides, or is an accumulation of the linear cavity.
(Supplementary Note 7) The chemical reaction device according to any one of Supplementary Notes 1 to 4, wherein
the opto-electrical field confinement structure is a plasmon-polariton structure.
(Supplementary Note 8) A method for producing a chemical reaction device, the method including:
producing a structure including a mirror plane/substrate by forming a mirror plane on a substrate;
producing a structure including a protective film/mirror plane/substrate by forming a protective film on the mirror plane;
producing a structure including a spacer/protective film/mirror plane/substrate by arranging a spacer defining a cavity length on the protective film;
producing a Fabry-Pérot cavity structure including a substrate/mirror plane/protective film/spacer/protective film/mirror plane/substrate by laying a structure including the protective film/mirror plane; substrate on top of a structure including the spacer/protective film/mirror plane/substrate; and
producing the chemical reaction device according to Supplementary Note 5 or 6 by housing the Fabry-Pérot cavity structure in an enclosure including an inlet, an outlet, and a chamber for storing the Fabry-Pérot cavity structure.
(Supplementary Note 9) A method for producing a chemical reaction device, the method including:
producing an acid-soluble-glass-filled glass tube by filling acid-soluble glass in a glass tube;
producing a thinned acid-soluble-glass-filled glass tube from the acid-soluble-glass-filled glass tube;
producing a thinned acid-soluble-glass-filled glass tube accumulation by aligning one or more of the thinned acid-soluble-glass-filled glass tubes in such a way that tube axes are parallel to one another and fusion-bonding the thinned acid-soluble-glass-filled glass tubes by heating;
producing a re-thinned acid-soluble-glass-filled glass tube accumulation from the thinned acid-soluble-glass-filled glass tube accumulation;
producing a re-thinned glass tube accumulation by dissolving the acid-soluble glass from the re-thinned acid-soluble-glass-filled glass tube accumulation by acid; and
producing an accumulation of the linear cavity according to Supplementary Note 6 by forming a mirror plane inside each re-thinned glass tube constituting the re-thinned glass tube accumulation.
(Supplementary Note 10) The method for producing a chemical reaction device according to Supplementary Note 9, further including
housing an aggregate of the linear cavity in an enclosure including an inlet, an outlet, and a chamber for storing an aggregate of the linear cavity.
(Supplementary Note 11) The method for producing a chemical reaction device according to (Supplementary Note 9 or 10, further including
forming a protective film on the mirror plane after forming the mirror plane inside the each re-thinned glass tube.
(Supplementary Note 12) The method for producing a chemical reaction device according to any one of Supplementary Notes 9 to 11, wherein
the thinned acid-soluble-glass-filled glass tube is produced by drawing the acid-soluble-glass-filled glass tube in a tube-axis direction by heating.
(Supplementary Note 13) The method for producing a chemical reaction device according to any one of Supplementary Notes 9 to 12, wherein
the re-thinned acid-soluble-glass-filled glass tube accumulation is produced by drawing the thinned acid-soluble-glass-filled glass tube accumulation in a tube-axis direction by heating.
The present invention is applicable to various industrial fields using a chemical reaction, such as chemistry, medical treatment/medicine, iron manufacturing/metallurgy, electronics, automobiles, shipbuilding, transportation, aerospace, and social infrastructure industries. It is expected that the present invention will be utilized in environment-conscious industries such as production of energy storage materials, typified by hydrogen, ammonia, and methanol, for substituting fossil fuel, a catalyst substituting rare metals typified by platinum and rhodium for NOx elimination, a processing system decomposing hazardous chemical materials typified by industrial effluents and sooty smoke, and production of ecological materials synthesized from common chemical products and biologically-derived raw materials. Furthermore, it is also expected that the present invention will be used in industrial fields related to social contribution since the present invention is applicable to a purification system performing bactericidal/detoxifying actions and artificial organs typified by an artificial kidney and an artificial liver, by activating a vibrational mode of a biological material constituting a bacterium and a virus and a vibrational mode of a human metabolite, and is also applicable to low-cost production of new antibiotics, generic drugs, or the like, and safe and secure provision of heat sources such as a non-flame-type heat source and a thermoelectric generator unit.
Number | Date | Country | Kind |
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2016-165849 | Aug 2016 | JP | national |
This application is a National Stage of International Application No. PCT/JP2017/030028 filed Aug. 23, 2017, claiming priority based on Japanese Patent Application No. 2016-165849 filed Aug. 26, 2016, the disclosures of which are incorporated herein in their entirety by reference.
Filing Document | Filing Date | Country | Kind |
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PCT/JP2017/030028 | 8/23/2017 | WO | 00 |