Sonochemical Approach to Synthesis of Co-B Catalysts and Hydrolysis of Alkaline NaBH4 Solutions

Abstract

Co-B catalysts are promising candidates for hydrogen evolution via hydrolysis of alkaline sodium borohydride (NaBH4) solutions. In the present paper, a sonochemical approach was investigated for synthesis of Co-B catalysts and hydrolysis of alkaline NaBH4 solutions. Sonochemical application on synthesizing process improved the intrinsic and extrinsic properties of Co-B catalysts such as crystal, spectral, surface area, pore volume, pore diameter, and particle size. Co-B catalysts prepared by sonochemical approach possessed smaller particle size, higher surface area, and higher pore volume than the Co-B catalysts prepared by coprecipitation synthesis. The effects of sonochemical process on hydrolysis of alkaline NaBH4 solutions were investigated by Arrhenius theory. It was clearly demonstrated that the advantages of alkaline NaBH 4 solution sonohydrolysis provide superficial effects on hydrogen evolution kinetic as maximum H-2 generation rate (HGR) and minimum activation energy (E-a).