Facile construction of robust Ru-Co3O4 Mott-Schottky catalyst enabling efficient dehydrogenation of ammonia borane for hydrogen generation

Abstract

Developing efficient catalysts for the dehydrogenation of ammonia borane (AB) is important for the safe storage and controlled release of hydrogen, but it is a challenging task. In this study, we designed a robust Ru-Co3O4 catalyst using the Mott-Schottky effect to induce favorable charge rearrangement. The self-created electron-rich Co3O4 and electron-deficient Ru sites at heterointerfaces are indispensable for the activation of the B-H bond in NH3BH3 and the OH bond in H2O, respectively. The synergistic electronic interaction between the electron-rich Co3O4 and electron-deficient Ru sites at the heterointerfaces resulted in an optimal Ru-Co3O4 heterostructure that exhibited outstanding catalytic activity for the hydrolysis of AB in the presence of NaOH. The heterostructure had an extremely high hydrogen generation rate (HGR) of 12238 mL min−1 gcat-1 and an expected high turnover frequency (TOF) of 755 molH2 molRu-1 min−1 at 298 K. The activation energy needed for the hydrolysis was low (36.65 kJ mol−1). This study opens up a new avenue for the rational design of high-performance catalysts for AB dehydrogenation based on the Mott-Schottky effect.