Alumina nanofiber-stabilized ruthenium nanoparticles: Highly efficient catalytic materials for hydrogen evolution from ammonia borane hydrolysis

Effective catalysts for hydrogen generation from ammonia borane (AB) hydrolysis should be developed for the versatile applications of hydrogen. In this study, ruthenium nanoparticles (NPs) supported on alumina nanofibers (Ru/Al2O3-NFs) were synthesized by reducing the Ru(Ш) ions impregnated on Al2O3-NFs during AB hydrolysis. Results showed that the Ru NPs with an average size of 2.9 nm were uniformly dispersed on the Al2O3-NFs support. The as-synthesized Ru/Al2O3-NFs exhibited a high turnover frequency of 327 mol H2 (mol Ru min)−1 and an activation energy of 36.1 kJ mol−1 for AB hydrolysis at 25 °C. Kinetic studies showed that the AB hydrolysis catalyzed by Ru/Al2O3-NFs was a first-order reaction with regard to the Ru concentration and a zero-order reaction with respect to the AB concentration. The present work reveals that Ru/Al2O3-NFs show promise as a catalyst in developing a highly efficient hydrogen storage system for fuel cell applications.