No abstract

We demonstrate a concept of potentially inexpensive sunlight-powered watersplitting reactors using a fixed Al-doped SrTiO 3 photocatalyst. A panel reactor filled with only a 1-mm-deep layer of water was capable of rapid release of product gas bubbles without forced convection. A flat panel reactor with 1 m 2 of lightaccepting area retained the intrinsic activity of the photocatalyst and achieved a solar-to-hydrogen energy conversion efficiency of 0.4% by water splitting under natural sunlight irradiation.

We demonstrate that the application of nanoparticulate indium tin oxide as a transparent and electrochemically inert conductive mediator allows the efficient and extensible Z-scheme water splitting by printable photocatalyst sheets. Water splitting into hydrogen and oxygen with the solar-to-hydrogen energy conversion efficiency of 0.4% can be realized without the need for vacuum processes during fabrication and operation by readily accessible screen printing. Appropriate combinations of materials will enable scalable, cost-effective, and thus practical solar fuel production through photocatalytic Z-scheme water splitting.