▎ 摘　　要

We report a solution-phase synthesis of 16 nm CuNi nanoparticles (NPs) with the Cu/Ni composition control. These NPs are assembled on graphene (G) and show Cu/Ni composition dependent catalysis for methanolysis of ammonia borane (AB) and hydrogenation of aromatic nitro (nitrile) compounds to primary amines in methanol at room temperature. Among five different CuNi NPs studied, the G-Cu36Ni64 NPs are the best catalyst for both AB methanolysis (turnover frequency (TOF) of 49.1 mol(H2) mol(CuNi)(-1) min(-1) and an activation energy (E-a) of 24.4 kJ/mol) and hydrogenation reactions (conversion yield of >97%). The G-CuNi compound represents a unique noble-metal-free catalyst for hydrogenation reactions in a green environment without using pure hydrogen.