Study of Ni and Pt Cocatalysts in Photocatalytic Hydrogen Evolution for InP-Based Quantum Dots

InP/ZnSe/ZnS core/shell/shell quantum dots (CSS-QDs) have already demonstrated considerable research potential in photocatalytic hydrogen evolution. To boost the photocatalytic hydrogen evolution activity of CSS-QDs, this work evaluated the impacts of Ni and Pt cocatalysts on catalytic performance, alongside their chemical behaviors under reaction conditions. Compared with pristine CSS-QDs, Ni and Pt cocatalysts boosted the catalytic activity by ∼4.5-fold and ∼51.2-fold, respectively, with Pt delivering a breakthrough activity enhancement. Systematic experiments revealed that Ni remained predominantly in ionic form during the reaction, while Pt existed in the form of elemental and oxide nanoparticles anchored on the CSS-QDs surface. The stronger interfacial interaction and faster electron transfer between Pt and CSS-QDs accounted for the superior catalytic performance. This work further highlights the application potential of InP-based QDs in photocatalytic hydrogen evolution, and provides both experimental evidence and theoretical guidance for the design and optimization of high-efficiency cadmium-free photocatalytic hydrogen evolution systems.