Abstract
Cu <sub>x</sub> Ag <sub>y</sub> In <sub>z</sub> Zn <sub>k</sub> S <sub>m</sub> solid solutions, customized with RuO <sub>2</sub> or Rh <sub>1.32</sub> Cr <sub>0.66</sub> O <sub>3</sub> co-catalyst with a small energy band gap <2 eV were studied for photocatalytic CO <sub>2</sub> reduction to CH <sub>3</sub> OH under visible light. Significantly, 118.5 mol g <sup>-1</sup> h <sup>-1</sup> CH <sub>3</sub> OH yield was obtained with RuO <sub>2</sub> /Cu <sub>0.30</sub> Ag <sub>0.07</sub> In <sub>0.34</sub> Zn <sub>1.31</sub> S <sub>2</sub> under hydrogen effect. © 2011 The Royal Society of Chemistry.