Synergizing Mg Single Atoms and Ru Nanoclusters for Boosting the Ammonia Borane Hydrolysis to Produce Hydrogen.

Development of efficient catalysts with high HO molecule activation ability holds great importance for H production. Herein, enzyme-mimic Mg single atoms catalysts (SACs) coordinated by B/N-doped carbon nanotube (BNC), was constructed as a high-performance support for ruthenium (Ru) nano-clusters. Dual functions of Mg SACs were discovered, where the Mg atoms beneath Ru catalysts built an interfacial electron polarization, inducing electron transfer from Ru to the Mg-BNC support. In addition, the oxyphilic Mg SACs adjacent to the Ru catalysts could actively participate in HO adsorption. The combination of experimental characterization, reaction kinetics study and density functional theory (DFT) calculations validated a stronger intrinsic HO activation capability at the positive Ru sites. Meanwhile, the synergistic Mg SACs jointly contribute to the acceleration of the sluggish HO dissociation process in ammonia borane (AB) hydrolysis reaction, resulting in exceptional hydrogen production activity and catalytic stability, outperforming most state-of-the-art Ru-based catalysts. This work provides a new strategy for utilizing alkaline earth metals as both the electronic promoter and the reactant activator, offering inspiration for the development of advanced heterogeneous catalysts.