Small and well-dispersed Cu nanoparticles on carbon nanofibers: Self-supported electrode materials for efficient hydrogen evolution reaction

In this study, a facile and effective approach was demonstrated for designing and preparing small Cu nanoparticles (NPs) densely and uniformly distributed on carbon nano fibers (CNFs). Self-supported hybrid CuNPs/CNFs with three-dimensional (3D) architectures were prepared via electrospinning and thermal reduction processes. The hybrid CuNPs/CNFs were directly used as electrodes for an electrocatalytic hydrogen evolution reaction (HER), and they exhibited excellent activity, with a low onset potential of only 61 mV, an overpotential of 200 mV at 10 mA cm (-2), a small Tafel slope (152 mV dec(-1)) and a long-term stability in acidic electrolyte. The 3D self-supported architecture exhibited a high conductivity, a large specific surface area and a high porosity, all of which are beneficial for the access of electrolyte for the CuNPs and the release of the formed H-2, thereby reducing the overpotentials and accelerating the electrode kinetics. This work demonstrates that CuNPs/CNFs are promising candidates for the substitution of noble metal Pt-based materials in producing the HER from water. (C) 2016 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.