Hydrogen generation from hydrolysis of NaBH4 solution with efficient g-C3N4/Co–Mo–B/Ni foam catalyst

Abstract

Sodium borohydride (NaBH4) is considered to be a perfect material for hydrogen production in consideration of the high hydrogen capacity. However, the catalyst with low cost and high activity is the key to achieving dehydrogenation from the hydrolysis of NaBH4 solution. In this work, we successfully synthesized g-C3N4/Co–Mo–B/Ni foam catalyst by means of chemical deposition at 298 K. The catalytic property of g-C3N4/Co–Mo–B/Ni foam for NaBH4 hydrolysis was investigated via regulating the molar ratio of Co2+ and MoO42− (nCo2+:nMoO42−). The results disclosed that the obtained g-C3N4/Co–Mo–B/Ni foam showed the optimum catalytic property when the nCo2+:nMoO42− value was 1:1. Its hydrogen generation rate (HGR) and apparent activation energy (Ea) were respectively determined to be 9957.7 mL min−1·g−1 and 52.6 kJ mol−1 under visible light irradiation, which has obviously exceeded the performance under darkness (HGR = 8372.7 mL min−1·g−1, Ea = 55.8 kJ mol−1). It might attribute to the emergence of Mo2C during the preparation process which attracted the photoelectron transfer on g-C3N4, thus promoting the photocatalytic hydrolytic process of NaBH4 solution. Moreover, the smaller grain size and synergistic effect between multiple components could be another reason for heightening the catalytic dehydrogenation property of g-C3N4/Co–Mo–B/Ni foam catalyst.