Insights into boosting catalytic hydrogen evolution over Co doping Ru nanoparticles

Accurate regulation of surface chemical state on catalysts is crucial for achieving efficient performance but remains a major challenge. In this work, the lattice strain, d electronic state and ensemble effect of supported Ru catalysts are tuned via Co doping to boost the hydrogen evolution from ammonia borane (AB) hydrolysis. The optimized Ru0.6Co0.4/P25 composite displays outstanding catalytic performance with a turnover frequency of 443.7 min−1 in the absence of strong alkali. Experimental analysis and theoretical simulation reveal the boosting effect of RuCo alloy on the activation of AB originating from the compressed lattice strain, reduced d-band center of Ru via Co doping. The ensemble effect on optimized surface state leads to a bimolecular activation of H2O on Co atoms and AB on Ru atoms. Suitable adsorption strength of H* intermediates and reduced energy barrier of H2O dissociation induced by the electron interaction between Ru and Co atoms are responsible for the prominent catalytic activity over RuCo alloy. This research provides new insights into the catalytic mechanism and inspiration for the rational design of heterogeneous catalysts and energy storage materials.