Scheelite-type BaMoO4 and BaWO4 based dye sensitized photocatalytic hydrogen evolution by water splitting

Abstract

Nowadays, the development of cost-effective and stable catalyst has greatly drawn attention for electrocatalytic and photocatalytic hydrogen evolution reactions. Herein, photocatalytic hydrogen evolution has been investigated by using BaMoO4 and BaWO4 catalysts in the presence of triethanolamine and eosin-Y as a sacrificial agent and visible-light-sensitizer, respectively. These refractory metal-based oxides prepared by solid phase synthesis procedure have been characterized by structural, morphological, optical and electrochemical techniques, which are obtained with high crystallinity and adequate stoichiometric ratios. While the hydrogen evolution rate of BaMoO4 is higher than BaWO4 in the first hours of photocatalytic reaction, BaWO4 displays more stable activity for hydrogen evolution, which is reached 3.37 mmolg−1 after the 8 h of photocatalytic reaction. The proposed mechanism of dye-sensitized photocatalytic hydrogen evolution is explained by data obtained from optical and electrochemical properties.