High-Entropy Oxide-Derived Graphdiyne: Exploiting Lattice Distortion and Oxygen Vacancies for Robust Photocatalytic...

This research is dedicated to improving the efficacy and durability of graphdiyne (GDY), a novel 2D carbon allotrope, for applications in photocatalytic hydrogen generation. Addressing issues such as the relatively poor stability of GDY in practical applications, we innovatively employed a high-entropy oxide (HEO) to replace conventional copper substrates, successfully preparing an HEO-GDY composite. This was further integrated with Zn_0.5Cd_0.5S to construct the ZHG-10 photocatalyst. Experimental results demonstrate that ZHG-10 exhibits superior photocatalytic hydrogen evolution activity and cycling stability in comparison to GDY-based catalysts synthesized from Cu or Cu²⁺ precursors, achieving a hydrogen production rate of up to 7.59 mmol/g/h. Photoelectrochemical tests reveal that the multi-element chemical environment of HEO significantly enhances the separation efficiency of photogenerated charge carriers. Kelvin probe force microscopy (KPFM) analysis and density functional theory (DFT) calculations indicate that the multi-metal synergy and lattice distortion effects in HEO introduce numerous defective active sites (e.g., oxygen vacancies), which not only serve as efficient centers for hydrogen adsorption and activation but also significantly optimize interfacial charge transfer pathways. This study elucidates the dual functionality of HEO-GDY in enhancing charge carrier separation and providing abundant active sites, offering a new strategy for developing high-performance and durable GDY-based photocatalytic systems.