Photoelectrochemical water splitting can convert solar energy into hydrogen which is an ideal way to utilize and store solar energy. A p-n tandem cell is considered as the most promising solar water splitting cell due to its high theory conversion efficiency, low cost and photoelectrode material flexibility. However, solar conversion efficiency of a tandem cell is still low in the experiment because of poor performance in a single photoelectrode. In this review, we have introduced some effective approaches to improve the performances of photoelectrodes by reducing recombination of photogenerated carriers in the bulk or on the surface, and suppressing back reaction. Moreover, we have also summarized recent progress of some p-type semiconductor photocathodes, such as Si, InP, CuIn1-x GaxS(Se)2 and Cu2ZnSnS4. Accordingly, we constructed a promising p-Cu2ZnSnS4(CuIn1-xGaxS(Se)2)/n-Ta3N5(Fe2O3)photoelectrode and obtained an efficient photoelectrochemical tandem cell with low cost.
Graphical Abstract
Keywords
Photoelectrochemical water splitting cells, Photocathodes, Si, InP; CuIn1-xGaxS(Se)2; Cu2ZnSnS4
