Mechanism for formation of NaBH 4 proposed as low-pressure process for storing hydrogen in borosilicate glass–sodium solid system: a hydrogen storage material

Abstract

The mechanism for the formation of sodium borohydride (NaBH\(_{\boldsymbol{4}})\) was investigated for its ability to store hydrogen in the borosilicate glass–sodium (BSG–Na) solid system under low hydrogen pressure. BSG, which was prepared by melting borax with silica, was used as the starting material in the BSG–Na system that would be prepared to store hydrogen. It was observed that the mechanism for storing hydrogen in the BSG–Na solid system consisted of six steps and when the BSG–Na system was heated under a pressure of 4 atm, which was created through the use of hydrogen atmosphere, the storage of hydrogen occurred at nearly 480°C for approximate duration of 200 min, with the excellent yield (97%). In addition, the hydrogen storage capacity of the NaBH\(_{\boldsymbol{4}}\) sample was measured using the Au–PS structure, which was designed as a mini-hydrogen cell. It was determined that the minimum amount of NaBH\(_{\boldsymbol{4}}\) to generate the maximum volume of hydrogen gas was 12 mg/ml at 270 mV.