Enhanced catalytic activity of Co–B/glassy carbon and Co–B/graphite catalysts for hydrolysis of sodium borohydride

• Graphite and glassy carbon supported Co–B catalysts were synthesized.
• The Co–B loading procedure affected the final activity.
• Catalysts prepared by precipitation route showed better performance.
• The apparent activation energy was 47.3 kJ/mol for the Co–B/GC–red.

This study focuses on the evaluation of catalytic activity of cobalt boride catalysts supported on graphitic and amorphous carbon derivatives with low surface area, namely graphite and glassy carbon, prepared by two different routes. The hydrogen generation rates over catalysts synthesized by conventional impregnation reduction and novel pre–reduction precipitation approach were compared for hydrolysis of alkaline sodium borohydride solution. In reduction precipitation route, unlike conventional method, Co–B colloidal particles were first synthesized via reduction of cobalt (II) ion and precipitated onto a carbon support. This simple, one–pot synthesis method significantly improves hydrogen generation volume. Structural properties and morphology of the catalyst powders were carried out by analysis techniques. Furthermore, variations of hydrogen generation rate with reaction temperature, concentration of NaOH and NaBH4 were also examined.

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