Enhanced photocatalytic hydrogen production through p-n heterojunction interface engineering using Prussian blue analogue-derived Co–Cu–P with graphdiyne (g-CnH2n-2) crystalline/amorphous

More efficient hydrogen production can be achieved by rationally designing heterojunction photocatalysts and constructing interactions between photocatalysts. Herein, The CoP/Cu 3 P (Co–Cu–P) nanocubes were designed using Prussian blue analogue (PBA) as a template through the calcination phosphating method. The novel crystalline-amorphous Co–Cu–P/GDY p-n heterostructures photocatalyst was prepared by a stir-assisted low-temperature water bath method. Under visible light irradiation, the hydrogen evolution efficiency of the Co–Cu–P/GDY-3 heterostructures reached 4790.0 μmol g −1  h −1 , surpassing that of GDY (523.9 μmol g −1  h −1 ) and Co–Cu–P (2458.5 μmol g −1  h −1 ). The remarkable hydrogen evolution activity of the composite catalyst can be attributed to the presence of p-n heterojunction, while the crystalline-amorphous structure promotes efficient interfacial charge transfer. Additionally, the rough and porous nature of the Co–Cu–P/GDY heterostructures surface facilitates mass transfer and hydrogen diffusion during photocatalysis. The charge transfer pathway of the p-n heterojunction was confirmed through various characterizations, including photoluminescence spectroscopy (PL), ultraviolet photoelectron spectroscopy (UPS), valence band X-ray photoelectron spectroscopy (VB-XPS), density functional theory (DFT) calculations, and other relevant techniques. This study offers a fresh perspective on designing PBA derivatives with graphdiyne (GDY) to construct heterostructure photocatalysts for enhanced photocatalytic performance.