Bimetallic CuNi@NC/SiO2 as Air-Stable and Efficient Catalysts for the Hydrolysis of Ammonia Borane.

The development of air-stable non-noble metal catalysts with high efficiency for hydrogen production from ammonia borane (AB) is crucial for advancing the hydrogen economy. In this work, Prussian blue analogs-derived air-stable CuxNiy@NC/SiO2 catalysts have been synthesized by a facile precipitation and thermal decomposition method. The optimized Cu1Ni6@NC/SiO2 exhibits the best hydrogen production performance at room temperature, being 5 times more active than Cu1Ni6@NC and superior to other CuxNiy@NC/SiO2 catalysts. Beyond the reactivity, Cu1Ni6@NC/SiO2 exhibits outstanding durability and antioxidant properties, maintaining its catalytic activity unchanged even after 6 months of air exposure. Characterization tools indicated that the enhanced performance and durability of the Cu1Ni6@NC/SiO2 catalyst originated from a combination of the synergistic effect of Ni-Cu alloying and the core-shell structure. Moreover, Cu1Ni6@NC/SiO2 also exhibits high efficiency and excellent recyclability toward the hydrogenation of adiponitrile and 2-methylglutaronitrile at ambient conditions on coupling with AB dehydrogenation. This research not only provides a simple strategy for the construction of air-stable non-noble metal catalysts for AB hydrolysis, but also offers a promising way for the design of heterogeneous non-noble metal catalysts with excellent oxygen resistance for industrial applications.