Unravelling the synergy in platinum-nickel bimetal catalysts designed by atomic layer deposition for efficient hydrolytic dehydrogenation of ammonia borane

Bimetal catalysis has been one of the major categories in heterogeneous catalysis field, and the efficient and durable catalysts can be well achieved by the bimetal synergy. Herein we report a remarkable achievement of both dehydrogenation activity of ammonia borane and durability by controllably engineering Pt-Ni interfacial sites via the Pt and the following NiO atomic layer deposition strategy, which can also realize the controllable synthesis of other Pt-M (M=Co, Cu, Fe and Zn) bimetal catalysts. Multiple characterization techniques, kinetic-isotopic analyses and density functional theory calculations were employed to unravel the nature of the Pt-Ni synergy. Experimental and theoretical results reveal that the decoration of nickel species on the Pt nanoparticles constructing the targeted Pt-Ni interfacial sites could lower the reaction activation energy, promote the adsorption, activation and dissociation of H 2 O molecules, and facilitate the desorption of hydrogen atoms, resulting in the doubly enhanced activity with a turnover frequency value of 751.6 mol H2 mol Pt -1 min -1 and the remarkably improved durability. Our work offers an alternative and general strategy for the rational design of bimetal catalysts with specific interfacial structure and provides fundamental guidance for in-depth understanding of the bimetal synergy. The PtNi/CNTs bimetal catalysts with controllable interfacial sites present the dramatically boosted hydrogen evolution activity and improved durability due to the remarkable Pt-Ni synergy • Ultrafine PtNi/CNTs bimetal nanocatalysts with controllable interfacial sites were synthesized by ALD. • The significant enhancement of both dehydrogenation activity and durability was achieved by the remarkable Pt-Ni synergy. • The nature of Pt-Ni synergy is elucidated by combining multiple characterizations, kinetic-isotopic analyses and DFT calculations. • The constructed Pt-Ni interfacial sites lower the reaction E a , promote the activation of H 2 O molecules, and facilitate the desorption of H 2 molecules.