Broadband photocatalysts enabled by 0D/2D heterojunctions of near-infrared quantum dots/graphitic carbon nitride nanosheets

Abstract

A heterojunction made of 0D near-infrared (NIR)-responsive PbS@CdS@ZnS core@shell@shell quantum dots (PCZ QDs) and 2D graphitic carbon nitride (g-C3N4) nanosheets was rationally constructed herein. In addition to some typical advantages of 0D/2D composites, such as short required charge-diffusion distance and high charge mobility, our designed PCZ QDs/g-C3N4 photocatalysts offer additional beneficial features. The broadband optical absorption of high-quality PCZ QDs highly dispersed on g-C3N4 nanosheets and their strong interaction yield efficient charge transfer between them and endow PCZ QDs/g-C3N4 with high photocatalytic activity from ultraviolet to NIR regions. With the optimized QDs loading level, the achieved, normalized rate constant is higher than the best-reported value for NIR-driven photocatalysis. PCZ QDs/g-C3N4 possesses good recycling performance and no metal release was detected in the solution after photocatalysis. This work highlights the great potential of QDs/g-C3N4 0D/2D photocatalysts in realizing high-efficiency broadband photocatalysis and functional optoelectronic devices for full solar spectrum exploitation.