Effect of manufacturing conditions on properties of electroless deposited Co–P/Ni foam catalyst for hydrolysis of sodium borohydride solution

The effects of the deposition time and coating bath with various pH and temperatures on the deposition rate, hydrogen generation rate per deposited catalyst of 1 g, surface morphology, catalyst particle distribution, and microstructure of electroless deposited Co–P/Ni foam catalysts were investigated. The degree of the effects of the parameters was in the following order: pH > temperature > deposition time. The effects of heat treatment temperature on the durability and catalytic activity were also investigated. Durability increased slightly in response to heat treatment, but hydrogen generation reduced owing to sodium sintering and oxide film formation. The optimum conditions were 12.0 (pH), 50 °C (temperature), and 30 min (deposition time) without heat treatment. The weight percent of the deposited catalyst and hydrogen generation rate per deposited catalyst of 1 g under the optimum conditions were 4.86 wt% and 1.49 L/min g (deposited catalyst), respectively. The apparent activation energy of the catalyst manufactured under the optimum conditions was 46.8 kJ/mol. The manufacturing conditions considerably affected the catalyst properties.

► Electroless deposited Co–P/Ni foam catalyst for flow-type hydrogen generator. ► We investigate the effect of manufacturing conditions on the catalyst properties. ► The degree of the effects of the parameters was: pH > temperature > deposition time. ► Heat treatment increases durability, but decreases catalytic activity. ► The manufacturing conditions considerably affected the catalyst properties.