Amorphous Ni-Fe-Co-P-B nanosheets as efficient electrocatalyst for oxygen evolution reaction

Abstract

Non-noble metal electrocatalysts with hierarchically structural design and heteroatom-doped is highly urgent for high-efficiency, low-cost electrochemical water splitting systems. Herein, this paper uses a simple and low-cost method to synthesize amorphous carbon-based Ni-Fe-Co-B-P composite material as efficient OER catalyst. Specifically, the catalytic performance can be enhanced through processes such as etching-recombination-reduction. First, we use ZIF-67 as the precursor to provide Co source and carbon source. Fe and Ni are creatively incorporated into the Co3O4 lattice as auxiliary metal atoms. Then, the above three metal oxides were simultaneously reduction with NaH2PO2 and NaBH4. Although this is the first time that MOF-based materials have been treated with P and B, the resulting samples are chemically stable. The obtained amorphous carbon-based material Ni-Fe-Co-B-P benefits from the advantages of its structure and composition, showing that the electron density is rearranged around the center of the catalytic metal atom and the energy barrier formed by the intermediate is reduced by weakening the metal-metal bond, thereby exhibiting excellent electrochemical performance. The overpotential to afford the current density of 10 mA cm-2 (268 mV) and the small Tafel slope (51.83 mV dec-1) show a predatorily competitive advantage compared with commercially available RuO2 (284 mV and 69.34 mV dec-1 respectively).