Simple synthesis and efficient photocatalytic hydrogen production of WO3-WS2 and WO3–WS2–MoS2

Abstract

Facile preparation of efficient photocatalysts is one of the challenges to realizing the practical application of photocatalysis technology. In this paper, binary composite WO3-WS2 and ternary composite WO3–WS2–MoS2 were easily prepared through simple one-step acidification-thermal decomposition (abbreviated as AT) of ammonium tetrathiotungstate (ATT) and ammonium tetrathiomolybdate (ATM) just using the inevitable formation of WO3 during the acidification of ATT. Especially, their photocatalytic hydrogen production performances were determined and the reasons for their activity differences were investigated systematically based on XRD, SEM, TEM, and XPS characterizations. The results showed that on the whole, these two composites possess better performance than both pure MoS2 and WS2, as well as our previously reported WO3-WS2 (1637.8 μmol h−1 g−1). Besides, the average hydrogen evolution rate of WO3-WS2 (5998.6 μmol h−1 g−1) is higher than that of WO3–WS2–MoS2 (4907.2 μmol h−1 g−1). Moreover, for the ternary composites, when the content of W and Mo is close, the change in W to Mo ratio has no obvious impact on the hydrogen production performance. Finally, a performance comparison of different preparation methods manifests that the one-step AT method is the simplest and most effective. This work can offer useful guidance for the preparation and photocatalytic application of both WS2 and MoS2-based composites.