Pt Single Atoms Embedded in the Ni2P Nanocrystal Surfaces as Highly Active Catalysts for Hydrogenation of Nitriles to Primary Amines

Abstract

The construction of well-defined heteroatomic pait-site catalysts with high performance holds significant implications for elucidating catalytic reaction mechanisms and developing advanced industrial catalysts. Herein, we report a highly active and selective nitrile hydrogenation catalyst by embedding Pt single atoms in the surface of Ni₂P nanocrystals (denoted as Pt₁-Ni₂P/SiO₂-V_P), thereby creating Pt₁-Ni^δ+ pair sites. In the hydrogenation of benzonitrile, Pt₁-Ni₂P/SiO₂-V_P exhibited substantially enhanced catalytic activity compared to its single-component counterparts.By integrating catalytic and kinetic studies, we demonstrated that alkaline etching generates P vacancies on the Ni₂P surface, enabling precise anchoring of Pt atoms to form the Pt₁-Ni^δ+ pairsite configuration. During catalysis, the Pt₁ site acted as the active center for H₂ activation, and the synergistic effect of Pt₁-Ni^δ+ pair sites led to significantly higher activity in nitrile hydrogenation reactions than the Ni₂P/SiO₂ catalyst, which contains only Ni^δ+ site. This work provides a rational design strategy for pair-site catalysts, with potential applicability to a broader range of catalytic systems.