Metallic Co2C: A Promising Co-catalyst To Boost Photocatalytic Hydrogen Evolution of Colloidal Quantum Dots

Transition-metal carbide (TMC), because of its electronic conductivity, chemical stability, and physical properties, has aroused widespread interest in catalysis. Here, we have systematically studied the photocatalytic hydrogen (H-2) evolution of metallic cobalt carbide (Co2C) by a combination of theoretical and experimental investigations. In terms of intrinsic proton reduction property of the Co2C (020) facet and facile interficial electron transfer, the assembled architecture of quantum dots (QDs)/Co2C can give a rate of similar to 18 000 mu mol g(-1)h(-1) (lambda = 450 nm), using TMC as co-catalysts and an apparent quantum yield of similar to 2.7% of photocatalytic H-2 evolution, an, similar to 10-fold enhancement, compared with bare QDs under identical conditions. Our results indicate that Co2C with suitable morphology and facet exposure can work as a co catalyst to achieve photocatalytic H-2 evolution.