Accurately measuring the hydrogen generation rate for hydrolysis of sodium borohydride on multiwalled carbon nanotubes/Co-B catalysts

Multiwalled carbon nanotubes supported cobalt-boron catalysts (Co-B/MWCNT) were developed via the chemical reduction of aqueous sodium borohydride with cobalt chloride for catalytic hydrolysis of alkaline NaBH4 solution. The hydrogen generation (HG) rates were measured on an improved high-accuracy, low-cost and automatic HG rate measurement system based on the use of an electronic balance with high accuracy. The HG of Co-B/MWCNT catalyst was investigated as a function of heat treatment, solution temperature, Co-B loading and supporting materials. The catalyst was mesoporous structured and showed lower activation energy of 40.40 kJ mol(-1) for the hydrolysis of NaBH4. The Co-B/MWCNT catalyst was not only highly active to achieve the average HG rate of 5.1 l min(-1) g(-1) compared to 3.1 l min(-1) g(-1) on Co-B/C catalyst under the same conditions but also reasonably stable for the continuous hydrolysis of NaBH4 solution. (C) 2008 International Association for Hydrogen Energy. Published by Elsevier Ltd. All rights reserved.