Gold nanorods/g-C3N4 heterostructures for plasmon-enhanced photocatalytic H-2 evolution in visible and near-infrared light

摘要

Recently, broad spectrum (visible and near-infrared (NIR)) light utilization has aroused widespread attention in the research of photocatalysis. While g-C3N4, highly stable, cheap and easily synthesized, shows H-2 evolution activity under visible light irradiation, it doesn't perform under NIR light irradiation. Here we report an Au nanorods (NRs)/g-C3N4 heterostructure with Au nanorods on g-C3N4's surface. The most exciting feature of designed Au NRs/g-C3N4 heterostructures is that Au nanorods themselves are excited by visible and NIR light, which produce hot electrons and inject into g-C3N4. The photocatalytic H-2 evolution rate of Au NRs/g-C3N4 heterostructures (350.6 mu mol g(-1) h(-1)) is nearly 4 times higher than that of g-C3N4 with Pt as cocatalyst (68.9 mu mol g(-1) h(-1)) under visible light illumination. The improved photocatalytic activity is ascribed to the increasing visible light-absorbing capacity of transverse surface plasmon resonance (TSPR) of Au nanorods and improved charge separation of Au NRs/g-C3N4 heterostructure. Even more important, Au NRs/g-C3N4 heterostructures achieve NIR photocatalytic H-2 evolution performance (63.1 mu mol g(-1) h(-1)), owing to the longitudinal SPR (TSPR) effect of Au nanorods induced NIR light harvesting ability. (C) 2019 Elsevier Inc. All rights reserved.