Precision Electronic Tuning of Gold Nanoclusters: A Generalizable Strategy for Enhanced Hydrogen Evolution...

Atomically precise gold nanoclusters hold promise in electrocatalysis, but postsynthetic electronic structure manipulation improves the hydrogen evolution reaction (HER). Herein, we develop a mild heterogeneous Pt doping strategy by substituting one Pt atom in [Au₈(DPPP)₇Cl₂]⁺ (DPPP = 1,3-bis(diphenylphosphino)propane). The doped [Au₇Pt(DPPP)₇Cl₂]⁺ retains the original ligand coordination and structural integrity as confirmed by ESI-MS, NMR, and TEM. Pt doping selectively modulates the electronic environment of reduction-active sites, evidenced by a 100 mV positive shift in reduction potential and Au 4f XPS binding energy elevation without altering oxidation-active metallic cores. This electronic reconfiguration optimizes H* adsorption energy, enabling exceptional HER performance: 0.22 V lower onset potential and 5.6-fold higher current density versus the undoped analog. [Au₇Pt(DPPP)₇Cl₂]⁺ outperforms the undoped nanocluster and platinum on carbon (Pt/C), with higher double-layer capacitance (4.66 mF·cm^-2), lower charge transfer resistance, excellent 24 h stability, and enhanced electrochemical active surface area, confirming practical HER potential. This work establishes heterogeneous metal atom doping as a generalizable approach for electronic fine-tuning of nanocluster catalysts.