Ultrafine cobalt nanoparticles supported on carbon nanospheres for hydrolysis of sodium borohydride

Abstract

Abstract Sodium borohydride (NaBH4) is an ideal chemical carrier of hydrogen due to its high hydrogen release capacity via hydrolysis, however the reaction is restricted by a competent catalyst. Herein, we present an efficient catalyst – ultrafine non-noble Co nanoparticles supported on carbon nanospheres (CNSs) (CNSs@Co), for hydrogen generation from NaBH4 hydrolysis in alkaline media. The ultrafine Co nanoparticles distribute evenly over the surface of the CNSs by adjusting solubility of a by-product – NaBO2 within ethanol. The as-prepared CNSs@Co catalyst has a glorious catalytic activity for hydrogen evolution of NaBH4. It shows a high hydrogen generation rate (HGR) of 7447 mL H 2 . min − 1 ⋅ g M − 1 at 30 °C, and a low activation energy of 40.79 kJ mol−1. Besides, the catalyst exhibits a stable cycling capability in a consecutive cycling test. The outstanding catalytic performance of the CNSs@Co catalyst could attribute to the ultrafine size of the Co nanoparticles (∼7 nm) and its uniform dispersion supported by the CNSs. We believe the catalyst together with its synthetic method will provide a probable strategy to promote the hydrogen generation from NaBH4.