Strong Metal‐Support Interaction Modulation between Pt Nanoclusters and Mn₃O₄ Nanosheets through Oxygen Vacancy Control to Achieve High Activities for Acidic Hydrogen Evolution

The optimization of metal‐support interactions is used to fabricate noble metal‐based nanoclusters with high activity for hydrogen evolution reaction (HER) in acid media. Specifically, the oxygen‐defective Mn 3 O 4 nanosheets supported Pt nanoclusters of ≈1.71 nm in diameter (Pt/V·‐Mn 3 O 4 NSs) are synthesized through the controlled solvothermal reaction. The Pt/V·‐Mn 3 O 4 NSs show a superior activity and excellent stability for the HER in the acidic media. They only require an overpotential of 19 mV to drive −10 mA cm −2 and show negligible activity loss at −10 and −250 mA cm −2 for >200 and >60 h, respectively. Their Pt mass activity is 12.4 times higher than that of the Pt/C and even higher than those of many single‐atom based Pt catalysts. DFT calculations show that their high HER activity arises mainly from the strong metal‐support interaction between Pt and Mn 3 O 4 . It can facilitate the charge transfer from Mn 3 O 4 to Pt, optimizing the H adsorption on the catalyst surface and promoting the evolution of H 2 through the Volmer–Tafel mechanism. The oxygen vacancies in the V·‐Mn 3 O 4 NSs are found to be inconducive to the high activity of the Pt/V·‐Mn 3 O 4 NSs, highlighting the great importance to reduce the vacancy levels in V·‐Mn 3 O 4 NSs.