Co0.8Cu0.2MoO4 Microspheres Composed of Nanoplatelets as a Robust Catalyst for the Hydrolysis of Ammonia Borane

Catalytic hydrolytic dehydrogenation of chemical hydrides is a safe and efficient way to provide hydrogen fuel for new energy vehicles and portable electronic devices. Currently, cost-efficient and high performance catalysts must be developed before the large-scale application of this hydrogen production technology can proceed. In this work, we prepared a series of CoxCu1-xMoO4, microspheres composed of nanoplatelets by a green approach free of any organics, such as surfactant, complexing agent, or organic solvent. For the first time, the catalytic activity of CoxCu1-xMoO4 in the hydrolytic dehydrogenation of ammonia borane (AB) was investigated. It is found that there is a synergistic effect between CoMoO4 and CuMoO4 in CoxCu1-xMoO4 toward the hydrolytic dehydrogenation of AB. Among those CoxCu1-xMoO4, catalysts, Co0.8Cu0.2MoO4 exhibits the highest catalytic activity with a turnover frequency of 55.0 mol(H2), min(-1) mol(catalyst)(-1), which is one of the most active noble-metal-free catalysts toward AB hydrolysis. It is revealed that the active species are the CoCu alloy nanoparticles supported on the Co0.8Cu0.2MoO4 microsphere. Additionally, the Co0.8Cu0.2MoO4 catalyst demonstrates good reusability, making it a robust catalyst for AB hydrolysis to generate hydrogen in practical applications.