A Comparative Study for Sodium Borohydride Dehydrogenation and Electrooxidation on Cerium and Cobalt Catalysts

Abstract

In the present study, Co/CNT and Ce/CNT catalysts are prepared via sodium borohydride (NaBH4) reduction method. Co/CNT and Ce/CNT catalysts are examined to the dehydrogenation and electrooxidation of NaBH4. NaBH4 dehydrogenation activities of these Co/CNT and Ce/CNT catalysts are performed in alkaline environment. 5% Co/CNT catalyst exhibits superior hydrogen evolution compared with other catalysts. Activation energy is calculated using Arrhenius equation. Initial rate for this catalyst is found as 1700 ml H-2 g(cat)(-1) min(-1). As a result of the kinetic calculations, the activation energy of the catalyst is calculated as 44,68775 kj/mol. The degree of reaction (n) is found to be 0.5 by trial and error. In conclusion, 5% Co/CNT catalyst is a promising catalyst for hydrogen production from NaBH4. Cyclic voltammetry (CV) analysis is utilized to examine the electrochemical activity of the catalysts for NaBH4 electrooxidation. 0.1% Co/CNT catalyst has 0.38 mA cm(-2) (3181 mA mg(-1) Co) specific activity.