Facile fabrication of rhodium/nanodiamond hybrid as advanced catalyst toward hydrogen production from ammonia–borane

Abstract

Hydrogen generation through ammonia–borane (AB) hydrolysis has been regarded as one of the most promising pathways to tap renewable green energy. The design and synthesis of highly effective catalysts toward hydrogen production from aqueous AB is of paramount significance. Here, the facile synthesis of Rh nanoparticles (NPs) immobilized on nanodiamond (nano-DA) and concomitant AB hydrolysis to produce hydrogen was successfully achieved. The in situ generated Rh/nano-DA exhibited excellent catalytic activity toward AB hydrolysis, with a high turnover frequency (TOF) value of 729.4 min−1 at 25 °C and a low activation energy of 25.6 kJ mol−1. Moreover, the catalyst could be reused four times. The unique properties of DA with abundant oxygen-containing groups enable the homogeneous distribution of small and surface-clean Rh NPs on the nano-DA surface, which can supply abundant accessible active sites for hydrogen evolution from AB hydrolysis. This study demonstrated that nano-DA can be applied as an ideal matrix to deposit efficient Rh nanocatalyst toward hydrogen evolution reaction.