High-entropy layered double hydroxides tailor Pt electron state for promoting acidic hydrogen evolution reaction

Despite the advancement of the Pt-catalyzed hydrogen evolution reaction (HER) through oxophilic metal-hydroxide surface hybridization, its stability in acidic solutions remains unsatisfactory. This is primarily due to excessive aggregation of active hydrogen, which hinders subsequent hydrogen desorption, coupled with the poor operational stability of metal hydroxides. In this study, we have designed Pt nanoparticles-modified NiFeCoCuCr high-entropy layered double hydroxides (Pt/HE-LDH) that exhibit exceptional catalytic activity toward HER in acidic electrolytes. Our findings reveal that the built-in electric field (BIEF) between Pt and HE-LDH facilitates the charge redistribution at Pt/HE-LDH interface, driven by the difference in work function. Additionally, effective hydrogen spillover from Pt nanoparticles to HE-LDH bidirectionally optimizes the Gibbs free energy for hydrogen adsorption. Furthermore, the interactions among the multi-metal sites, along with high entropy-induced phase stability, contribute to superior stability in acidic electrolytes. This work not only presents a straightforward strategy for enhancing hydrogen spillover from Pt but also improves the durability of metal hydroxides under acidic HER conditions.