Photocatalytic apparatus

Abstract

A photocatalytic apparatus is provided that uses a photovoltaic action for both electrodes and conjugates a photocatalytic action with the photovoltaic action to efficiently perform material transformation on the basis of a redox reaction on the electrodes using light energy. A photocatalytic apparatus includes a first electrode functioning as an anode and a second electrode functioning as a cathode. The first electrode includes a first transparent conductive substrate having light transmittivity and electrical conductivity, a first light power generation layer that is disposed on the first transparent conductive substrate and absorbs light to generate electrons and holes, and a photocatalytic layer that is disposed on the first light power generation layer and catalyzes an oxidation reaction when being irradiated with light. The second electrode includes a second transparent conductive substrate having light transmittivity and electrical conductivity, a second light power generation layer that is disposed on the second transparent conductive substrate and absorbs light to generate electrons and holes, and a catalytic layer that is disposed on the second light power generation layer and catalyzes a reduction reaction.

What is claimed is: 
     
         1 . A photocatalytic apparatus comprising:
 a first electrode disposed in an electrolytic solution or in steam and functioning as an anode; and   a second electrode electrically connected to the first electrode and disposed in an electrolytic solution or in steam, the second electrode functioning as a cathode, wherein   the first electrode includes a first transparent conductive substrate having light transmittivity and electrical conductivity, a first light power generation layer that is disposed on the first transparent conductive substrate and absorbs light to generate electrons and holes, and a photocatalytic layer that is disposed on the first light power generation layer and catalyzes an oxidation reaction when being irradiated with light, and   the second electrode includes a second transparent conductive substrate having light transmittivity and electrical conductivity, a second light power generation layer that is disposed on the second transparent conductive substrate and absorbs light to generate electrons and holes, and a catalytic layer that is disposed on the second light power generation layer and catalyzes a reduction reaction.   
     
     
         2 . The photocatalytic apparatus according to  claim 1 , wherein
 the first electrode includes a first electron transport layer between the first transparent conductive substrate and the first light power generation layer, the first electron transport layer selectively transporting electrons.   
     
     
         3 . The photocatalytic apparatus according to  claim 1 , wherein
 the second electrode includes a charge transport layer between the second transparent conductive substrate and the second light power generation layer, the charge transport layer transporting charge.   
     
     
         4 . The photocatalytic apparatus according to  claim 1 , wherein
 the second electrode includes a second electron transport layer between the second light power generation layer and the catalytic layer, the second electron transport layer selectively transporting electrons.   
     
     
         5 . The photocatalytic apparatus according to  claim 4 , wherein
 the second electrode includes a conductive reflection layer between the second electron transport layer and the photocatalytic layer, the conductive reflection layer having electrical conductivity and reflecting irradiation light.   
     
     
         6 . The photocatalytic apparatus according to  claim 1 , wherein
 a promotor is supported or a promotor layer is laminated on the photocatalytic layer.   
     
     
         7 . The photocatalytic apparatus according to  claim 1 , wherein
 electrode elements of the first electrode are divided into cell structures by an insulator.   
     
     
         8 . The photocatalytic apparatus according to  claim 1 , wherein
 electrode elements of the second electrode are divided into cell structures by an insulator.   
     
     
         9 . The photocatalytic apparatus according to  claim 1 , further comprising:
 a recovery mechanism that recovers a product generated by the first electrode; and   a recovery mechanism that recovers a product generated by the second electrode.   
     
     
         10 . The photocatalytic apparatus according to  claim 1 , further comprising:
 a feeding mechanism that feeds a reactant of the oxidation reaction to the first electrode; and   a feeding mechanism that feeds a reactant of the reduction reaction to the second electrode.   
     
     
         11 . The photocatalytic apparatus according to  claim 1 , wherein
 the first electrode oxidizes water to generate oxygen, and the second electrode reduces carbon dioxide.