Patent Application
20140158186
The present invention generally relates to a solar cell, and more particularly to a dye-sensitized solar cell (DSSC).
A solar cell is a device which converts solar energy to electrical energy. A dye-sensitized solar cell is a new type of solar cell.
The dye-sensitized solar cell mainly comprises a photo electrode, a counter electrode and an electrolytic solution. The electrolytic solution is disposed between the photo electrode and the counter electrode. The photo electrode comprises nano-particles of TiO2 with dye adsorption. When sunlight is irradiated to the photo electrode, electrons of dye of the photo electrode are transferred from a ground state to an excited state. Then, the electrons are transferred to the counter electrode for achieving electron transportation. The dye which loses the electrons receives electrons from the electrolytic solution, after which it returns to the ground state.
Generally speaking, a catalytic layer is coated on the counter electrode for enhancing efficiency of the dye-sensitized solar cell. Currently, platinum (Pt) is a mostly used material for the catalytic layer. Selecting the platinum for the catalytic layer not only provides a better catalytic surface but also decreases a voltage loss due to an overpotential.
However, since the platinum is expensive, a lot of researches propose various materials for substituting for the platinum, such as cobalt sulfide, nickel sulfide and so on. These proposed materials are not abundant resources in the earth. Accordingly, cost of the dye-sensitized solar cell cannot be reduced.
Consequently, there is a need to solve the above-mentioned problem that the material used for the catalytic layer of the counter electrode is expensive and rare such that the cost of the dye-sensitized solar cell cannot be reduced.
An object of the present invention is to provide a counter electrode and a dye-sensitized solar cell using the same, which are capable of solving the problem that the expensive and rare platinum is utilized for the catalytic layer, such that the cost of the dye-sensitized solar cell cannot be reduced
To achieve the above-mentioned object, an aspect of the present invention is to provide a counter electrode. The counter electrode comprises a conductive layer and a catalytic layer. The catalytic layer is formed on a surface of the conductive layer. The catalytic layer comprises FeS2.
To achieve the above-mentioned object, another aspect of the present invention is to provide a dye-sensitized solar cell. The dye-sensitized solar cell comprises a photo electrode, a counter electrode and an electrolytic solution. The counter electrode is disposed correspondingly to the photo electrode. The counter electrode comprises a conductive layer and a catalytic layer. The catalytic layer is formed on a surface of the conductive layer facing the photo electrode. The catalytic layer comprises FeS2. The electrolytic solution is disposed between the photo electrode and the counter electrode.
In the counter electrode and the dye-sensitized solar cell of the present invention, the FeS2 is utilized as the material of the catalytic layer. Since the FeS2 is abundant mine in the earth, the manufacturing cost of the dye-sensitized solar cell can be significantly reduced, thereby effectively solving the problem that the platinum or other noble metals are not acquired easily due to high cost.
The technical scheme of the present invention will be further described in detail as follow by giving embodiments with reference to the accompanying drawings.
Please refer to
The dye-sensitized solar cell of the present invention comprises a photo electrode 10, a counter electrode 20 and an electrolytic solution 30.
The photo electrode 10 comprises a conductive layer 100 and a porous semiconductor layer 102. The porous semiconductor layer 102 is formed on a surface of the conductive layer 100. More particularly, the porous semiconductor layer 102 is formed on the surface of the conductive layer 100 of the photo electrode 10 facing the counter electrode 20. The porous semiconductor layer 102 comprises a plurality of metal oxide nano-particles with dye adsorption. In the present embodiment, the metal oxide nano-particles with dye adsorption are titanium dioxide nano-particles (TiO2). In another embodiment, the metal oxide nano-particles with dye adsorption may be other suitable metal oxide nano-particles. The dye is known by one skilled in the art of the present invention and not repeated herein.
The counter electrode 20 is disposed correspondingly to the photo electrode 10 and comprises a conductive layer 200 and a catalytic layer 202. The catalytic layer 202 is formed on a surface of the conductive layer 200. More particularly, the catalytic layer 202 is formed on the surface of the conductive layer 200 facing the photo electrode 10. In the present embodiment, the conductive layer 200 is a flexible and transparent substrate. For instance, the conductive layer 200 is, but not limited to, an indium tin oxide (ITO) substrate, a fluorine-doped tin oxide (FTO) substrate and so on. In another embodiment, the conductive layer 200 may be a non-transparent and/or rigid substrate.
A key feature of the dye-sensitized solar cell of the present invention is that the catalytic layer 202 comprises iron pyrites (FeS2). Preferredly, the FeS2 comprises nanocrystals of FeS2. The nanorystals of FeS2 have a particle size of from about 1 nanometer (nm) to about 100 nm. The counter electrode 20 comprises the conductive layer 200 and the nanorystals of FeS2 coated on the conductive layer 200 (such as the above-mentioned ITO substrate). The nanorystals of FeS2 and the conductive layer 200 are together formed a nano-composite material. In another embodiment, the FeS2 serving as the catalytic layer 202 has a particle size of from about 100 nm to about 100 micrometers (μm).
In the dye-sensitized solar cell of the present invention, the FeS2 is utilized for the catalytic layer 202, thereby substituting for the expensive platinum serving as the catalytic layer of the counter electrode in the prior arts. Since the catalytic ability of the FeS2 is excellent and the FeS2 is abundant mine in the earth, the manufacturing cost of the dye-sensitized solar cell can be significantly reduced. Moreover, the nanorystals of FeS2 have a geometric shape with high roughness, such that the catalytic ability may be further enhanced.
In one embodiment, the above-mentioned nanorystals of FeS2 may be spin-coated on a conductive substrate, for instance, an ITO substrate or an FTO substrate, in a room temperature, thereby forming a film with high catalytic ability. The above-mentioned process is a soluble process. Since the counter electrode 20 together formed by the nanorystals of FeS2 and the ITO substrate may be manufactured via the soluble process, the counter electrode 20 may be applied to a counter electrode of a soft dye-sensitized solar cell.
In the above-mentioned embodiment, the FeS2 may be spin-coated on the conductive substrate, for instance, the ITO substrate or FTO substrate, thereby forming a uniform and transparent film. Accordingly, the uniform and transparent film may be applied to a back-illuminated type dye-sensitized solar cell and applied to a fuel cell, paint, a catalytic and transparent film and so on.
The electrolytic solution 30 is disposed between the photo electrode 10 and the counter electrode 20. The electrolytic solution 30 comprises a redox couple consisting of iodide ions and triiodide ions. The FeS2 utilized by the present invention has excellent catalytic ability to catalyze reduction of the triiodide ions. In another embodiment, the electrolytic solution 30 comprises a redox couple consisting of ferricyanide/ferrocyanide (Fe(CN)6 4−/3−) or a redox couple consisting of polysulfide electrolyte (S2−/Sx2−).
The dye-sensitized solar cell of the present invention may further comprise a sealing layer 40. The sealing layer 40 is disposed between the photo electrode 10 and the counter electrode 20 and at least disposed at two sides of the electrolytic solution 30 and the porous semiconductor layer 102. The sealing layer 40 is utilized for sealing the electrolytic solution 30 and the porous semiconductor layer 102 for preventing the electrolytic solution 30 from leaking. In another embodiment, the sealing layer 40 may be disposed at two sides of the porous semiconductor layer 102, the catalytic layer 202 and the electrolytic solution 30 for sealing the porous semiconductor layer 102, the catalytic layer 202 and the electrolytic solution 30.
Please refer to
Please refer to
Please refer to
Please refer to
Please refer to
Please refer to
In the counter electrode and the dye-sensitized solar cell of the present invention, the FeS2 is utilized as the material of the catalytic layer. Since the FeS2 is abundant mine in the earth, the manufacturing cost of the dye-sensitized solar cell can be significantly reduced, thereby effectively solving the problem that the platinum or other noble metals are not acquired easily due to high cost. Moreover, the nanorystals of FeS2 have a geometric shape with high roughness, such that the catalytic ability may be further enhanced.
As is understood by a person skilled in the art, the foregoing preferred embodiments of the present invention are illustrative rather than limiting of the present invention. It is intended that they cover various modifications and similar arrangements be included within the spirit and scope of the appended claims, the scope of which should be accorded the broadest interpretation so as to encompass all such modifications and similar structure.
| Number | Date | Country | Kind |
|---|---|---|---|
| 101146084 | Dec 2012 | TW | national |
