A General Method for Large-Scale Fabrication of Metal Nanoparticles Embedded N-doped Carbon Fiber Cloth with Highly Efficient Hydrogen Production in All pH Range

Ion implantation is a facile surface modification technology for greatly tailoring the surface electron structure of materials, which is very important for catalytic activity. Here we report a new universal synthesis of stable, large-scale N-doped carbon fiber cloth embedded with non-noble metal nanoparticles (CN@(Ni, Fe and Co)) by ion implantation for largely enhanced hydrogen evolution reaction (HER) activity under acidic (0.5 M H2SO4), neutral (0.5 M phosphate buffer, PH = 7) and basic solution (1M KOH). From the polarization curves, the overpotentials of current density for CN@Ni at 10 mA/cm2 decrease obviously from 710, 838 and 717 mV to 381, 589 and 532 mV in acidic, neutral and basic solution, respectively. Density functional theory (DFT) calculations also demonstrate that the Gibbs free energy (ΔGH∗) for H∗ adsorption of CN@Ni is much closer to the optimal value of ΔGH∗ = 0.15 eV compared with 1.84 eV of C and 0.86 eV of CN. The method is general and we demonstrate it using Fe+ and Co+ ions implantation into carbon fiber cloth to fabricate metal nanoparticles embedded carbon fiber cloth. Furthermore, this controlled technique is promising for industrial production of noble-metal-free HER electrocatalysts with large scale, low cost and high efficiency.