Carbon Dots-Capped Bimetallic Phosphide for Boosted Photoelectrocatalytic Hydrogen Evolution Coupled with Ethylene Glycol Oxidation

Photoelectro-catalytic hydrogen evolution reaction (HER) coupled with ethylene glycol oxidation reaction (EGOR) is crucial for the green hydrogen production and the upcycling of waste plastics. However, its efficiency is limited by photoelectric conversion efficiency and catalytic efficiency of photoelectrochemical electrodes. Herein, carbon dots (CDs) with strong photocatalytic activity were capped onto Fe 2 P and MoP with excellent catalytic activity, the constructed Fe 2 P/MoP@CDs presents boosted photoelectric HER, EGOR and HER//EGOR performance. Experimental results demonstrate that the lamellar structure of Fe 2 P/MoP@CDs presents abundant photo-electrocatalytic active sites, appropriate visible spectrum absorption response, and energy band structure. Meanwhile, Fe 2 P/MoP@CDs exhibits strong redox ability with a conduction band of -2.42 eV and a valence band of 1.25 eV, which is beneficial for the improved catalytic performance. These are ascribed to the reduced band gap width of Fe 2 P/MoP, the improved separation and migration efficiency of photogenerated electron-hole pairs by the capped CDs, which can increase the photoelectric conversion efficiency, contributing to the improved activity and stability of photo-electrocatalysis. This work provides a novel strategy to develop advanced bifunctional photoelectric catalysts for HER coupled EGOR, which helps to improve the efficiency of green hydrogen evolution and provide an effective way to upcycle the waste plastic.