Chinese Journal of Catalysis ›› 2019, Vol. 40 ›› Issue (11): 1668-1672.DOI: 10.1016/S1872-2067(19)63326-7

• Communication • Previous Articles     Next Articles

Metal selenides for photocatalytic Z-scheme pure water splitting mediated by reduced graphene oxide

Shanshan Chena, Takashi Hisatomia, Guijun Mab, Zheng Wanga, Zhenhua Panb, Tsuyoshi Takataa, Kazunari Domena,b   

  1. a Center for Energy & Environmental Science, Shinshu University, 4-17-1 Wakasato, Nagano-shi, Nagano 380-8553, Japan;
    b Department of Chemical System Engineering, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
  • Received:2019-01-22 Revised:2019-02-17 Online:2019-11-18 Published:2019-09-06
  • Supported by:
    This work was financially supported by the Artificial Photosynthesis Project of the New Energy and Industrial Technology Development Organization (NEDO) and Grant-in-Aids for Scientific Research (A) (No. 16H02417) and Young Scientists (A) (No. 15H05494) from the Japan Society for the Promotion of Science (JSPS).

Abstract: Exploration of novel narrow bandgap semiconductors for overall water splitting is vital for the realization of practical solar H2 production. In the work, solid solutions of zinc selenide and copper gallium selenide with absorption edge wavelengths ranging from 480 to 730 nm were developed. Using these metal selenides as H2-evolving photocatalysts, CoOx/BiVO4 as the O2-evolving photocatalyst, and reduced graphene oxide as the electron mediator, all-solid-state Z-scheme overall pure water splitting systems were constructed. The rate of photocatalytic H2 evolution from aqueous solutions containing Na2S and Na2SO3 as the electron donors was evaluated while employing these selenide photocatalysts at various Zn/(Zn+Cu) and Ga/Cu molar ratios. The data demonstrate that efficient Z-scheme overall water splitting was significantly correlated to the photoelectrochemical performance of the selenide photocatalysts acting as photocathodes, rather than the photocatalytic activities of these materials during the sacrificial H2 evolution.

Key words: Hydrogen production, Photocatalysis, Selenide, Water splitting, Z-scheme