Low-Cost Ni₃B/Ni(OH)₂ as an Ecofriendly Hybrid Cocatalyst for Remarkably Boosting Photocatalytic H₂ Production over g-C₃N₄ Nanosheets

Abstract

Photocatalytic hydrogen (H2) evolution is an appealing and promising means for productive solar-to-chemical energy conversion. g-C3N4(CN) is an exciting semiconductor, but its undesirable pristine activity seriously limited the potential for large-scale application. Herein, we, for the first time, demonstrated that the low-cost nickel boride (Ni3B)/nickel hydroxide (Ni(OH)2) is an ecofriendly hybrid cocatalyst for remarkably boosting visible-light H2 evolution over CN. The maximum H2 evolution rate of CN–3%Ni3B–2%Ni(OH)2 reaches 352.43 μmol g–1 h–1, with an apparent quantum efficiency of 0.70% at 405 nm, which is much higher than that of pure CN, only 0.1 μmol g–1 h–1. In the cycling experiment, the ternary CN–3%Ni3B–2%Ni(OH)2 shows relatively high stability in the triethanolamine solution. More importantly, the promoted charge separation and reduced overpotential were demonstrated to be responsible for the significantly boosted visible-light H2 generation over CN nanosheet-based photocatalysts due to the loading of Ni3B/Ni(OH)2 cocatalyst. It is believed that this study will provide a suitable strategy to rationally design a low-cost, facile-fabrication, and ecofriendly cocatalyst for efficient visible-light hydrogen evolution of CN nanosheet-based photocatalysts.