Fabrication of ultrafine metastable Ru-B alloy for catalytic hydrogenation of NEC at room temperature

Liquid organic hydrogen carriers (LOCHs) hold considerable potential for large-scale and long-distance energy/hydrogen storage and transportation. However, due to the lack of efficient catalysts, harsh conditions are needed for the reversible hydrogen uptake and/or release of LOHCs. Herein, a one-pot method was developed to synthesize an ultrafine metastable Ru-B alloy, where the geometrical and electronic structure of Ru is well modulated by B. To our delight, the hydrogenation of N-ethylcarbazole (NEC, one of the promising LOHC candidates) could be catalyzed by Ru-B alloy with ca. 99 % yield to 12H-NEC at room temperature. To the best of our knowledge, this is the first example of realizing the hydrogenation of NEC at room temperature. Theoretical simulations indicate that the (0001) surface of Ru7B3 crystal may be the active site for the catalytic hydrogenation. This work shows the potency of metastable nanomaterials as efficient catalysts for chemical transformations which are kinetically challenging. [Display omitted] •A highly active and metastable Ru-B alloy was fabricated.•Room temperature hydrogenation of NEC was successfully achieved in the presence of the metastable Ru-B alloy.•Simulation results show that the (0001) surface of Ru7B3 crystal may be the active site for the catalytic hydrogenation.