Preparation, characterization and catalytic NaBH4 hydrolysis of Co-B hollow spheres

In this paper, we report on the preparation, characterization and catalytic NaBH4 hydrolysis of Co-B hollow spheres that were prepared through a template-assistant route. The structure, composition and morphologies of the as-prepared samples were characterized by XRD, ICP, SEM, TEM, XPS and BET. The as-synthesized amorphous and thermal-treated Co-B hollow spheres have a porous wall with the inner diameter of about 260 nm. The hydrogen release measurement demonstrates that the thermal-treated Co-B hollow spheres exhibit higher catalytic activity than that of the amorphous Co-B hollow spheres and the amorphous Co-B nanoparticles for the hydrolysis of NaBH4. The activation energies for the catalytic hydrolysis of NaBH4 were determined to be 45.5 and 58.6 kJ mol(-1) for the thermal-treated Co-B hollow spheres and the amorphous Co-B nanoparticles, respectively. This favorable result reveals that Co-B hollow spheres are promising catalysts for the hydrolysis of NaBH4 to release hydrogen. (C) 2008 Elsevier B.V. All rights reserved.