Co-Mn/TiO2 Catalyst to Enhance the NaBH4 Decomposition

Abstract

Developing catalyst to create a feasible system for NaBH₄ hydrolysis would increase the widespread use of clean energy producing fuel cell system. However, transfer difficulties such as; three phase reaction mechanism and reactant-side product solubility problems limit the promising properties of the hydrolysis systems. In this study Co_1-xMn_x bimetallic catalyst was produced and adhered on TiO₂ support by co-reducing method. Optimum NaOH concentration for the catalyst and reaction conditions was determined before the studies. In the experiments it was proved that only 40 mg of Co_0.7Mn_0.3/TiO₂ catalyst is highly active to decompose NaBH₄ at 20 °C. SEM-EDX results revealed that the catalyst homogeneity and active sites existence are valid after reaction. Released hydrogen was collected by inverse burette apparatus and maximum hydrogen generation rate was calculated as 43.6  at 20 °C. Investigations resulted that the reaction obeys first order kinetic on the basis of NaBH₄ and the activation energy is 38.7 kJ.mol^-1.

Keywords

• Bimetallic catalyst, hydrolysis, NaBH4

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