Dual chelates derived CoNiP as an efficient electrocatalyst for acidic hydrogen evolution reaction

Currently, developing efficient and cost-effective electrocatalysts for hydrogen evolution reaction (HER) is an enormously grand challenge. Herein, an N-doped carbon-encapsulated CoNiP (CoNiP-NC) is successfully prepared using a dual-chelate (ZIF-67@EDTA-Ni2+) precursor by a simple method. Benefiting from the synergistic effects among the redistributed charges, the rich porous structure, and the different chemical states of doped N in the CoNiP-NC, the optimized CoNiP-NC-600 shows an excellent electrocatalytic performance toward HER with an overpotential of 104.2 mV and a small Tafel slope of 71.4 mV/dec to derive a current density of 10 mA/cm(2) in 0.5 M H2SO4 solution. Moreover, due to the N-doped carbon shell protection, CoNiP-NC-600 exhibits considerably enhanced stability under the harsh conditions of a 60-h reaction. Density functional theory (DFT) calculations reveal that the optimized CoNiP-NC-600 not only enhances the adsorption of H2O but also decreases the desorption of formed H-2, essentially promoting the catalytic activity. It is believed that our developed method provides an effective and feasible route for constructing bimetallic phosphide electrocatalysts for hydrogen production.