Carbon-supported Ni1-x@Ptx (x=0.32, 0.43, 0.60, 0.67, and 0.80) core-shell nanoparticles as catalysts for hydrogen generation from hydrolysis of ammonia borane

We report on the carbon supported Ni core-Pt shell Ni1-x@Pt-x/C (x = 0.32, 0.43, 0.60, 0.67, and 0.80) nanoparticles as catalysts for hydrogen generation from hydrolysis of ammonia borane (NH3BH3). The catalysts are prepared through a polyol synthesis process with oleic acid as the surfactant. The structure, morphology, and chemical composition of the obtained samples are characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) equipped with energy dispersive X-ray (EDX), inductively coupled plasma emission spectroscopy (ICP), and nuclear magnetic resonance (NMR). The results show that the Ni core-Pt shell nanoparticles are uniformly dispersed on the carbon surface with the diameters of 2-4 nm, and furthermore, the catalysts show favorable performance toward the hydrolysis of NH3BH3. Among the nanoparticles, Ni-0.33@Pt-0.67/C displays the highest catalytic activity, delivering a high hydrogen release rate of 5469 mL min(-1) g(-1) and a low activation energy of 33.0 kJ mol(-1). (C) 2010 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved.