Patent Application
20130101501
The present invention relates to an iron oxide and a method for producing the iron oxide, especially relates to an urchin-like iron oxide and a method for producing the urchin-like iron oxide
Iron oxide, such as iron (III) oxide, is a popular material for producing an N-type semiconductor, has features of toxic-free property, light stability, and great shield capability and is widely applied in coating, catalytic, electrochemical and bioengineering fields. However, the electrochemical properties of iron oxide will be significantly affected by the particle size, pore structure and form of an iron oxide particle.
The iron oxide particle might be spheral shaped with nano or micro scale. Some researchers also try to produce screw or urchin-like shaped iron oxide. Methods for producing specific iron oxides include a hydrothermal synthesis and a template technique. The hydrothermal synthesis uses a metallic oxide to form a metal-surfactant precursor by reacting with a surfactant under a water-free environment. Then the metal-surfactant precursor is acted with a additive and some water so that the surfactant is self-arranged spontaneously and the metallic oxide undergoes a hydrolysis and poly-condensation process to form an urchin-like iron oxide (Du and Cao, 2008). The template technique uses a micro spheral-shaped sulfonate polystyrene as a hard template. The sulfonate polystyrene reacts with an iron-contained solution in a hydrothermal condition to form a urchin-shaped iron oxide. The final step is to remove the template by a sintering process.
The urchin-like iron oxides in accordance with the above mentioned methods just have urchin-shaped in geometry without uniform needle-arrangement. Otherwise, the process of the hydrothermal synthesis and the template formation of the template technique are highly complexity so that the production cost will be increased. The above two methods also have disadvantage of limiting operation requirement such as specific atmosphere controlled or solution formulated. Accordingly, it is difficult to precisely control multiple parameters of the iron oxide and to form a standardized urchin-like product.
The object of the present invention is to provide an inventive urchin-like iron oxide. The urchin-like iron oxide comprises an iron core has a surface and multiple needle-like elongations that are mounted on protruded form the surface of the iron core. The iron core is a fine powder and has nano scale in diameter. The needle-like elongation has high length and width ratio and could be broadly used in the electro-optical engineering and the catalytic field.
Another object of the present invention is to provide a method for producing an urchin-like iron oxide. The method has advantages of simplified operation and lowered expense. The method in accordance with the present invention is to stably heat an iron-contained powder under room temperature by a thermal oxidation. The surface of the iron-contained powder is slow oxidized to form an urchin-like iron oxide with multiple uniform distributed needle-like elongations protruded from the surface. The size of each needle-like elongation is easily adjusted and changed by controlling the heating temperature. The crystallized feature, length, diameter and appearance of the needle-like elongations of the urchin-like iron oxide are uniform. The ratio of the length and width of the needle-like elongation is higher that is suitable for applying in an optoelectronic field.
The above objects and advantages of the present invention will become more readily apparent to those ordinarily skilled in the art after reviewing the following detailed descriptions and accompanying drawings in which:
Please refer to
With reference to
providing a raw material (20): providing an iron-contained fine powder as the raw material;
heating and oxidation (21) the raw material: putting the iron-contained fine powder on a plate and heating the iron-contained fine powder to a specific temperature for a period.
In the heating and oxidation (21) step, the raw material is heated from room temperature to at least 220° C. for at least half hour, preferably the heating rate is 1 to 20° C. per minute. In one embodiment, the heating and oxidation (21) step is operated under atmosphere without applying a specific condition. In another embodiment, the heating and oxidation (21) step is operated under the oxygen concentration by at least 10 mole percentages.
The example 1 uses an iron powder as the raw material that is heated to 300° C. with the temperature is increased by 5° C. per minute. With reference to
The example 2 uses an iron powder as the raw material that is heated to 350° C. with the temperature is increased by 5° C. per minute and then keeps heating by 350° C. for a period. With reference to
The example 3 also uses an iron powder as the raw material that is heated to 400° C. with the temperature is increased by 5° C. per minute and then keeps heating by 400° C. for a period. With reference to
With refer to
With reference to
Accordingly, the method for producing an urchin-like iron oxide in accordance with the present invention has advantage of easy operation and efficiently decreases the operation expense and procedure. The ratio of the length and width of the needle-like elongation of the urchin-like iron oxide is higher for applying in an optoelectronic field.
| Number | Date | Country | Kind |
|---|---|---|---|
| 099138149 | Nov 2010 | TW | national |
This application is a Divisional of co-pending application Ser. No. 13/079,367, filed on Apr. 4, 2011, for which priority is claimed under 35 U.S.C. §120; and this application claims priority of Application No. 099138149 filed in Taiwan, R.O.C. on Nov. 5, 2010 under 35 U.S.C. §119; the entire contents of all of which are hereby incorporated by reference.
| Number | Date | Country | |
|---|---|---|---|
| Parent | 13079367 | Apr 2011 | US |
| Child | 13712579 | US |
