Hydrogen generation from catalytic hydrolysis of sodium borohydride using bimetallic Ni–Co nanoparticles on reduced graphene oxide as catalysts

Abstract

Preparation and characterization of bimetallic Ni–Co nanoparticle catalysts loaded on the reduced graphene oxide, denoted as Ni–Co/r-GO, for hydrogen generation from catalytic hydrolysis of sodium borohydride were studied. The reduced graphene oxide nanosheets were prepared from natural graphite. The Ni and Co metals were electrolessly deposited on the light-weighted reduced graphene oxide (r-GO) nanosheets. Process parameters affecting the hydrolysis reaction of NaBH4 in the presence of Ni–Co/r-GO catalysts, such as NaOH and NaBH4 concentrations, as well as catalyst loadings and reaction temperature, were investigated. A hydrogen production rate as high as ca. 1280 mL min−1 (g cat.)−1 could be obtained using the prepared Ni–Co/r-GO catalysts. The activation energy of the catalytic hydrolysis reaction of sodium borohydride was found at 55.12 kJ mol−1 from the system consisting of 10 wt% NaBH4 and 5 wt% NaOH as well as a catalyst loading at 0.1 g catalyst per g NaBH4.