Department of Chemical System Engineering, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
Japan Technological Research Association of Artificial Photosynthetic Chemical Process (ARPChem), 5-1-5 Kashiwanoha, Kashiwa-shi, Chiba 277-8589, Japan.
Nat Mater. 2016 Jun;15(6):611-5. doi: 10.1038/nmat4589. Epub 2016 Mar 7.
Photocatalytic water splitting using particulate semiconductors is a potentially scalable and economically feasible technology for converting solar energy into hydrogen. Z-scheme systems based on two-step photoexcitation of a hydrogen evolution photocatalyst (HEP) and an oxygen evolution photocatalyst (OEP) are suited to harvesting of sunlight because semiconductors with either water reduction or oxidation activity can be applied to the water splitting reaction. However, it is challenging to achieve efficient transfer of electrons between HEP and OEP particles. Here, we present photocatalyst sheets based on La- and Rh-codoped SrTiO3 (SrTiO3:La, Rh; ref. ) and Mo-doped BiVO4 (BiVO4:Mo) powders embedded into a gold (Au) layer. Enhancement of the electron relay by annealing and suppression of undesirable reactions through surface modification allow pure water (pH 6.8) splitting with a solar-to-hydrogen energy conversion efficiency of 1.1% and an apparent quantum yield of over 30% at 419 nm. The photocatalyst sheet design enables efficient and scalable water splitting using particulate semiconductors.
利用颗粒状半导体进行光催化水分解是一种具有潜在可扩展性和经济可行性的技术，可将太阳能转化为氢气。基于两步光激发析氢光催化剂（HEP）和析氧光催化剂（OEP）的 Z 型体系适合于利用太阳光，因为具有还原或氧化水活性的半导体都可以应用于水分解反应。然而，要实现 HEP 和 OEP 颗粒之间的电子有效转移是具有挑战性的。在此，我们提出了基于 La 和 Rh 共掺杂 SrTiO3（SrTiO3：La，Rh；参考文献）和 Mo 掺杂 BiVO4（BiVO4：Mo）粉末嵌入金（Au）层的光催化剂片。通过退火增强电子中继作用和通过表面修饰抑制不希望的反应，使纯水（pH 6.8）在 419nm 处的光解具有 1.1%的太阳能到氢的能量转换效率和超过 30%的表观量子产率。该光催化剂片设计能够利用颗粒状半导体实现高效和可扩展的水分解。
