Applied Catalysis B: Environmental, Vol.221, 243-257, 2018
The enhancement of CdS photocatalytic activity for water splitting via anti-photocorrosion by coating Ni2P shell and removing nascent formed oxygen with artificial gill
CdS photocorrosion seriously impeded its application in photocatalysis, especially for water splitting. Here we report new strategies to improve CdS photocorrosion resistance properties significantly by coating Ni2P shell and assembling an artificial gill to remove newly formed O-2 from water. Ni2P@CdS catalyst can achieve the over-all water splitting under visible light irradiation without addition of any sacrifice reagent and noble metal loading. Compared with CdS itself, the 10Ni(2)P@CdS photocatalyst exhibits excellent photocatalytic activity for hydrogen evolution (251.4 mu mol of H-2 in 180 min) with a high AQE (3.89% at 430 nm). This catalyst also presents high photocurrent, low overpotential (-0.32 V vs SCE), and long fluorescence lifetime (16.27 ns) of excited charges. Cd2+ ions concentration measured by ICP and long term stability results verified the anti-photocorrosion role of Ni2P shell on CdS during water splitting reaction. The activity and stability of 10Ni(2)P@CdS is even superior to typical 1Pt@CdS catalyst. Our results confirm CdS can be an active catalyst for photocatalytic hydrogen generation from water under visible irradiation if its stability is enhanced by protection of anti-photocorrosion over coating shell and removing the nascent formed oxygen from water.