# US 2008/0185037 A1 · Photo-Electric For A Dye-Sensitized Solar Cell Comprising A Meso-Porous Metal Oxide Thin Film And A Process For Preparation Thereof > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2008/0185037 A1 - Document ID: US20080185037A1 - Status: Published application - Kind: A1 - Application number: 11/966,048 - Filed: 2007-12-28 - Published: 2008-08-07 - Earliest claimed: 2007-01-04 - Assignees: Korea Institute of Science and Technology - Inventors: Kyung Kon KIM; Nam-Gyu Park; Ki Cheon Yoo; Wan In Lee; Yun Hee Lee - Web page: https://patentgrep.com/patent/US20080185037A1 ## CPC - H01G 9/2031: {comprising titanium oxide, e.g. TiO2 (H01G9/2036 takes precedence)} - H01G 9/2059: {comprising an organic dye as the active light absorbing material, e.g. adsorbed on an electrode or dissolved in solution} - Y02E 10/542: Dye sensitized solar cells - H01G: CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE (selection of specified materials as dielectric H01B3/00; capacitors having potential barriers H10D1/62, H10K10/10) - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION ## Abstract Disclosed is a photo-electrode for a dye-sensitized solar cell comprising a conductive substrate; a meso-porous metal oxide thin film formed on the surface of the conductive substrate; a porous film formed on the meso-porous metal oxide thin film and comprising metal oxide nanoparticles; and a photosensitive dye adsorbed on the surface of the porous film; and a process for preparation thereof. ## Claims ### Claim 1 A photo-electrode for a dye-sensitized solar cell comprising: a conductive substrate; a meso-porous metal oxide thin film formed on the surface of the conductive substrate; a porous film formed on the meso-porous metal oxide thin film and comprising metal oxide nanoparticles; and a photosensitive dye adsorbed on the surface of the porous film. ### Claim 2 (depends on 1) The photo-electrode of claim 1, wherein the metal oxide of the meso-porous metal oxide thin film or the porous film is selected from the group consisting of titanium (Ti) oxide, zirconium (Zr) oxide, strontium (Sr) oxide, zinc (Zn) oxide, indium (In) oxide, lanthanum (La) oxide, vanadium (V) oxide, molybdenum (Mo) oxide, tungsten (W) oxide, tin (Sn) oxide, niobium (Nb) oxide, magnesium (Mg) oxide, aluminum (Al) oxide, yttrium (Y) oxide, scandium (Sc) oxide, samarium (Sm) oxide, gallium (Ga) oxide, strontium-titanium (SrTi) oxide, and a mixture thereof. ### Claim 3 (depends on 1) The photo-electrode of claim 1, wherein the meso-porous metal oxide thin film has an average thickness of 1 to 5,000 nm. ### Claim 4 (depends on 1) The photo-electrode of claim 1, wherein the porous film has an average thickness of 10 to 20 μm. ### Claim 5 (depends on 1) The photo-electrode of claim 1, wherein the porous film has metal oxide nanoparticles having an average particle diameter of 1 to 500 nm. ### Claim 6 (depends on 1) The photo-electrode of claim 1, which further comprises a blocking layer having an average thickness of 1 to 5,000 nm formed on the meso-porous metal oxide thin film. ### Claim 7 A process for preparing a photo-electrode for a dye-sensitized solar cell comprising: (a) preparing a conductive substrate; (b) forming a meso-porous thin film comprising metal oxides on the surface of the conductive substrate; (c) forming a porous film comprising metal oxide nanoparticles on the meso-porous thin film; and (d) making a photosensitive dye to adsorb on the surface of the porous film. ### Claim 8 (depends on 7) The process of claim 7, wherein step (b) comprises preparing an alcoholic sol-gel solution containing a metal oxide precursor, a surfactant and hydrochloric acid, coating the solution on the conductive substrate, and heat-treating the resulting coating, to form the meso-porous thin film, wherein the metal oxide precursor is a titanium alkoxide. ### Claim 9 (depends on 8) The process of claim 8, wherein the titanium alkoxide is selected from the group consisting of titanium ethoxide, titanium butoxide, titanium isopropoxide, and a mixture thereof. ### Claim 10 (depends on 8) The process of claim 8, wherein the coating is conducted by spin coating, dip coating, or drop casting. ### Claim 11 (depends on 8) The process of claim 8, wherein the heat treatment is conducted at a temperature of 300 to 550° C. for a period from 10 minutes to 2 hours. ### Claim 12 (depends on 7) The process of claim 7, wherein step (c) comprises preparing a paste containing metal oxide nanoparticles, a polymer binder, and a solvent, coating the paste on the meso-porous thin film, and heat-treating the resulting coating, to form the porous film. ### Claim 13 (depends on 12) The process of claim 12, wherein the heat treatment is conducted at a temperature of 400 to 550° C. for a period from 10 to 120 minutes. ### Claim 14 (depends on 7) The process of claim 7, wherein step (d) comprises immersing the substrate having the meso-porous thin film and the porous film formed thereon in a solution containing a photosensitive dye for a period of 1 to 48 hours, to allow the photosensitive dye to adsorb on the surface of the porous film. ### Claim 15 (depends on 7) The process of claim 7, wherein the metal oxide of the meso-porous metal oxide thin film or the porous film is selected from the group consisting of titanium (Ti) oxide, zirconium (Zr) oxide, strontium (Sr) oxide, zinc (Zn) oxide, indium (In) oxide, lanthanum (La) oxide, vanadium (V) oxide, molybdenum (Mo) oxide, tungsten (W) oxide, tin (Sn) oxide, niobium (Nb) oxide, magnesium (Mg) oxide, aluminum (Al) oxide, yttrium (Y) oxide, scandium (Sc) oxide, samarium (Sm) oxide, gallium (Ga) oxide, strontium-titanium (SrTi) oxide, and a mixture thereof. ### Claim 16 (depends on 7) The process of claim 7, which further comprises the step of coating a metal oxide precursor solution on the meso-porous metal oxide thin film and heat treating the coating to form a blocking layer, which is carried out before step (b). ### Claim 17 (depends on 16) The process of claim 16, wherein the metal oxide precursor solution is obtained by dissolving 0.5 to 25 parts by weight of a metal oxide precursor in 100 parts by weight of a solvent, wherein the solvent is selected from the group consisting of methyl alcohol, ethyl alcohol, tetrahydrofuran, distilled water, and a mixture thereof; the metal oxide precursor is selected from the group consisting of titanium (IV) chloride, titanium (IV) isopropoxide, and titanium (IV) bis(ethylacetoacetato) diisopropoxide; and the concentration of the metal oxide precursor solution is in the range of 0.01 to 0.5 M. ### Claim 18 (depends on 1) A dye-sensitized solar cell comprising: a photo-electrode in accordance with claim 1; a counter electrode disposed opposite to the photo-electrode; and an electrolyte filled between the photo-electrode and the counter electrode. ### Claim 19 (depends on 7) A dye-sensitized solar cell comprising: a photo-electrode prepared by the method of claim 7; a counter electrode disposed opposite to the photo-electrode; and an electrolyte filled between the photo-electrode and the counter electrode.