Phosphating Cu/Graphdiyne Nanospheres for Improved Photocatalytic Hydrogen Production

The classical synthesis of graphdiyne (GDY) involves the cross-coupling reaction of hexaethynylbenzene on copper foil. However, due to the bulky nature of copper foil, stripping loss occurs. In this study, nanospherical copper powder was employed instead of copper foil for the preparation of Cu/graphdiyne (Cu/GDY) phosphide, which exhibits superior photocatalytic activity compared to copper as it efficiently absorbs light energy and converts it into chemical energy, thereby promoting hydrogen evolution reaction with photocatalysts. Moreover, cuprous phosphide demonstrates excellent stability during the photocatalytic process and is resistant to photocorrosion or oxidation. By adjusting the phosphating ratio through high-temperature phosphating, Cu/GDY-P containing Cu3P was obtained. The maximum hydrogen evolution rate under visible light reached 785.75 μmol g–1 h–1. Based on X-ray photoelectron spectroscopy (XPS) and density functional theory (DFT) results, a plausible photogenerated charge transfer mechanism in Cu/GDY-P is proposed herein. This work presents a straightforward and feasible strategy for treating Cu/GDY-P materials with significant implications for future researchers involved in preparing copper-based/GDY materials.