Carbon dots bridged Zn0.5Cd0.5S with interfacial amide bond facilitating electron transfer for efficient photocatalytic hydrogen peroxide production

Abstract

Photocatalytic H₂O₂ production has gained significant attention as an environmentally friendly approach. The key is to explore efficient photocatalysts with sufficient active sites and excellent electron transfer capacity. Herein, we propose a novel approach by incorporating carbon dots (CDs) on ethylenediamine capped Zn_0.5Cd_0.5S, which was bridged with an interfacial amide bond. Smooth transfer of photoinduced electrons from Zn_0.5Cd_0.5S to carbon dots via a high-speed electron channel is afforded by interfacial amide bond. A remarkable H₂O₂ yield with a rate of 252 μmol/h and an apparent quantum yield (AQY) of 31 % at 400 nm is achieved. Photoelectrochemical analysis and density function theory (DFT) calculation reveal CDs with abundant oxygenous functional groups as active sites, boosting activity and selectivity. This interfacial engineering strategy with the acceleration of electrons transfer and enhanced 2e^- selectivity can be applied to advanced photocatalytic systems for the achievement of valuable organics, environmental purification and new energy carriers.