Atomic-Scale Robust Modulation of Pt on Monolayer MoS2 for Enhanced on-Chip Hydrogen Evolution Reaction

Abstract

Maintaining high catalytic performance while maximizing metal atom utilization requires atomic-level modulation of catalyst microstructure in noble-metal catalyst design. On-chip microreactors enable precise measurements of catalytic activity in specific regions, advancing the understanding of structure-property relationships. Here, Pt single atoms (SAs), clusters, and sub-2.5 nm nanoparticles (NPs) are synthesized on monolayer MoS2 via defect-anchoring. On-chip electrochemical measurements during hydrogen evolution reaction (HER) demonstrated that Pt clusters-MoS2 exhibited superior activity, achieving a 94 mV overpotential at 10 mA cm−2, much lower than that of Pt SAs-MoS2 (202 mV) and Pt NPs-MoS2 (259 mV). Density functional theory calculations revealed that the electron transfer from MoS2 to Pt clusters altered H* adsorption site, yielding a near-zero Gibbs free energy for enhanced HER activity. The work reveals the structure-property relationships in Pt-modified MoS2 catalysts, guiding atom-efficient noble metal catalyst development for HER and emphasizing precise mapping between preparation, microstructure, and performance.