Low-cost and reusable iron- and nickel-based metal boride nanoparticles for efficient catalytic hydrolysis of sodium borohydride

Abstract

Development of efficient catalysts for hydrogen evolution reaction is of key importance for the safe storage and utilization of hydrogen from the hydrolysis of NaBH4. In this study, a series of nanocatalysts containing iron- and nickel-based metal borides were developed through a mechanochemical route followed by a wet milling step. The use of the mole ratio of metal chlorides to NaBH4 as 1:2 enabled the simultaneous formation of Ni3B and FeB phases, while the room-temperature synthesis method caused a uniform morphology with an average particle size and surface are of 70 nm and 41.8 m2/g, respectively. This powder showed the best catalytic performance compared to other samples with a hydrogen generation rate value of 758 ml H2 min−1 gcat−1 at room temperature and an activation energy of 40.8 kJ/mol. The catalyst performed good durability for each cycle and retained about 70% of its initial catalytic activity after 5 cycles. The availability of active iron, nickel, and boron species on the surface contributed to the enhancement of catalytic activity. As-prepared catalysts can be considered as low-cost and reusable materials for the efficient hydrolysis of sodium borohydride.