Efficient hydrolytic dehydrogenation of ammonia borane over ultrafine Ru nanoparticles supported on biomass-derived porous carbon

Abstract

Ammonia borane hydrolysis is a promising strategy for developing sustainable hydrogen energy. However, this reaction is not kinetically feasible at ambient temperature, thus developing a proper catalyst is indispensable. In this work, Porous carbon is facilely prepared from cattail fibers by using K2CO3, and then used to stabilize Ru nanoparticles. The effects of different synthesis parameters for the biomass-derived carbon supports (e. g. K2CO3 dosage and calcination temperature) and various catalytic reaction conditions (e. g. the amounts of the catalysts, ammonia borane and NaOH, and reaction temperature) on the hydrolysis rate of ammonia borane are investigated. Benefitting from the interconnected hierarchical pores of the optimal porous carbon (p-C), which was prepared with a mass ratio of 6 : 1 for K2CO3 to cattail fibers and calcined at 873 K, and the high dispersion of Ru nanoparticles, the optimal Ru/p-C catalysts exhibit excellent catalytic performance. The corresponding apparent activation energy (28.8 kJ mol−1) and turnover frequency (744.7 min−1 in alkaline solution) are superior to many catalysts previously reported. This work offers a competitive catalyst for the hydrolytic dehydrogenation of chemical hydrogen storage materials.