Self-standing 3D rose-like bimetallic oxides modified nitrogen-doped graphite aerogels as a robust catalyst for efficient oxygen evolution

Abstract

FeNi bimetallic oxides are considered as a potential catalyst candidate material for efficient oxygen evolution. However, low conductivity, rapid structural collapse, and metal ion release always lead to electrochemical performance and poor stability, which become major challenges in the electrochemical process. Herein, we synthesized self-standing 3D rose-like bimetallic oxides modified nitrogen-doped graphite aerogels (FeNiOx@N/GA) by the facile layer-by-layer self-assembled method. The unique 2D/3D structure composed of 2D ultrathin graphene nanosheets decorated 3D microflowers can provide a large active area and a rapid charge transfer rate. Moreover, both oxidation and nitrogen doping can improve the reaction kinetics of the material, thereby exhibiting higher catalytic activity. FeNiOX@N/GA exhibits excellent oxygen evolution reaction (OER) performance (η10=291 mV) and low Tafel slope (39 mV dec−1) in the 1 M KOH. This work can be expected to provide a novel and valid method for rational design and manufacture of advanced bimetallic oxides-based positive electrode toward efficient OER. Meanwhile, FeNiOx@N/GA is loaded on nickel foam and displays good electrochemical properties as an air-cathode in Zn-Air battery, demonstrating outstanding practicability.