Dendritic Co-Cu and Ni-Cu alloys were employed as hydrogen generation catalysts via hydrolysis of ammonia borane (NH3BH3, AB). Dendritic Co0.52Cu0.48 and Ni0.19Cu0.81 alloys were successfully synthesized with starch by a facile and efficient in situ method at room temperature. The structure, morphology, and chemical composition of the as-obtained samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) with energy dispersive X ray spectroscopy (EDX), transmission electron microscopy (TEM) inductively coupled plasma emission spectroscopy (ICP) and X-ray photoelectron spectroscopy (XPS). The characterization results revealed a dendritic and uniform distribution for the as-synthesized nanoparticles (NPs). Good performance towards the hydrolysis of AB was observed in all cases, although Co0.52Cu0.48 showed the highest hydrogen release rate (r, 2179 mL min(-1).g(-1) and the lowest activation energy (E-a, 37.3 kJ mol(-1)) among the samples prepared. The surface structure of the alloys and the reticular density of the different crystal faces were studied with the aim to explain the catalytic performance of the samples. (C) 2017 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.