A ternary Z-scheme WO3-Pt-CdS composite for improved visible-light photocatalytic H-2 production activity

摘要

Fabrication of advanced semiconductor system for photocatalytic water splitting into valuable hydrogen energy has attracted a lot of attention worldwide due to the increasing global energy crises. In this work, a ternary WO3-Pt-CdS composite was synthesized through coprecipitation and hydrothermal reactions. The ternary composite (i.e. WO3-PtCdS) showed a high hydrogen evolution rate of 390 mu mol h(-1) g(-1) exceeding CdS alone (27 mu mol h(-1) g(-1)), WO3-CdS (55 mu mol h(-1) g(-1)), and CdS-Pt (135 mu mol h-1 g-1). The enhanced photocatalytic activity is mainly attributed to the formation of Z-scheme heterojunction between WO3 and CdS, which results in the effective space charge separation. Meanwhile, the Pt in the as-prepared WO3-Pt-CdS plays an essential role as a bridge for accelerating the charge transportation between WO3 and CdS. This work provides another effective way of developing visible-light-driven photocatalysts for practical application.