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 pair-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+ pair-site 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+ sites. This work provides a rational design strategy for pair-site catalysts, with potential applicability to a broader range of catalytic systems.