g-CN foam/CuO QDs with excellent CO adsorption and synergistic catalytic effect for photocatalytic CO reduction.

A unique heterostructure is developed based on a 3D photoactive semiconductor and a 0D CuO QDs for superb photocatalytic reduction CO into CO. It reported a novel and simple method to prepare a 3D g-CN foam with micron-sized porous structures using ultrastable foam as a soft template for the first time. Moreover, CuO QDs are loaded onto 3D g-CN foam through a simple photodeposition strategy. Systematically characterization demonstrated that g-CN foam not only act as an excellent carrier for CuO QDs, but also greatly improve the photocatalytic performance by enhancing CO adsorption and gas transfer. Simultaneously, the rationally designed g-CN foam/CuO QDs exhibited notablely enhancement in photocatalytic performance with 3.9 times and 11 times higher than that of g-CN foam and bulk g-CN powder. The excellent photocatalytic activity can be attributed to the unique porous structure and the synergistic effect between g-CN foam and CuO QDs, which can speed up the transfer of charge carriers and urged the cumulation of photo-generated electrons on the CuO QDs. Our work provides new ideas for constructing 0D/3D hierarchical photocatalytic systems, which may provide guidance on designing efficient photocatalysts to maximize photocatalyst kinetics.