Three birds, one-stone strategy for fabrication of hierarchically arrayed Ru/B-U-TiO2 nanoribbon assemblies toward efficient hydrogen evolution

Abstract

Developing efficient strategies to promote Ru-catalysed hydrogen evolution from ammonia borane hydrolysis (ABH) are definitely desired considering the much lower price of Ru relative to the state-of-the-art Pt and Rh. Herein, a unique strategy with the “three birds, one stone” effect is developed to upgrade Ru-catalysed hydrogen evolution from ABH. This strategy involves the doping of boron (B) impurities into urchin-like TiO2 nanoribbon assemblies and subsequent deposition of uniformly distributed Ru nanoparticles (NPs) with ultrafine sizes. Three synergetic effects are induced by the B-doping of urchin-like TiO2 (B-U-TiO2) matrix: (a) the introduction of abundant superficial hydroxyl groups that facilitate the anchoring of ultrafine Ru NPs with high dispersion; (b) the creation of strong electronic interaction between the Ru NPs and B-U-TiO2 support; (c) the improvement in mass transport from the hierarchically arrayed nanoribbon assemblies and rich superficial hydroxyl groups. The unique hierarchically arrayed architecture and excellent structural features of Ru/B-U-TiO2 considerably boost the catalytic performance towards ABH for hydrogen evolution, achieving a high turnover frequency of 1287 min−1 and a high reusability with highly remained activity of the initial one after the 8th cycle. This study provides a new avenue to rationally fabricate efficient materials for catalytic hydrogen production.