CuNi Nanoparticles Assembled on Graphene for Catalytic\nMethanolysis of Ammonia Borane and Hydrogenation of Nitro/Nitrile\nCompounds

Abstract

We\nreport a solution-phase synthesis of 16 nm CuNi nanoparticles\n(NPs) with the Cu/Ni composition control. These NPs are assembled\non graphene (G) and show Cu/Ni composition-dependent catalysis for\nmethanolysis of ammonia borane (AB) and hydrogenation of aromatic\nnitro (nitrile) compounds to primary amines in methanol at room temperature.\nAmong five different CuNi NPs studied, the G-Cu₃₆Ni₆₄ NPs are the best catalyst for both AB methanolysis (turnover\nfrequency (TOF) of 49.1 mol_H₂ mol_CuNi^–1 min^–1 and an activation energy\n(<i>E</i>_a) of 24.4 kJ/mol) and hydrogenation\nreactions (conversion yield of >97%). The G-CuNi compound represents\na unique noble-metal-free catalyst for hydrogenation reactions in\na green environment without using pure hydrogen.