Dehydrogenation of Ammonia Borane by Platinum‐Nickel Dimers: Regulation of Heteroatom Interspace Boosts Bifunctional Synergetic Catalysis

Abstract

Regulation of the atom-atom interspaces of dual-atom catalysts is essential to optimize the dual-atom synergy to achieve high activity but remains challenging. Herein, we report an effective strategy to regulate the Pt₁ -Ni₁ interspace to achieve Pt₁ Ni₁ dimers and Pt₁ +Ni₁ heteronuclear dual-single-atom catalysts (HDSACs) by tailoring steric hindrance between metal precursors during synthesis. Spectroscopic characterization reveals obvious electron transfers in Pt₁ Ni₁ oxo dimers but not in Pt₁ +Ni₁ HDSAC. In the hydrolysis of ammonia borane (AB), the H₂ formation rates show an inverse proportion to the Pt₁ -Ni₁ interspace. The rate of Pt₁ Ni₁ dimers is ≈13 and 2 times higher than those of Pt₁ and Pt₁ +Ni₁ HDSAC, manifesting the interspace-dependent synergy. Theoretical calculations reveal that the bridging OH group in Pt₁ Ni₁ dimers promotes water dissociation, while Pt₁ facilitates the cleavage of B-H bonds in AB, which boosts a bifunctional synergy to accelerate H₂ production cooperatively.