FeNi Nanoparticles Embedded in Porous Nitrogen-Doped Graphene for Electrocatalytic Evolution of Hydrogen and Oxygen

Abstract

The thermal annealing method is regarded as a general and promising method for preparation of carbon-based electrocatalysts. However, this method always suffers from complex and harsh preparative conditions, such as high pyrolysis temperature, protective gas environment, and long synthesis period. Herein, a laser engraving method is introduced for preparation of porous nitrogen-doped graphene layer-enclosed FeNi nanoparticles (FeNi/PNGs), starting with metal organic frameworks (MOFs) as precursors. All the steps were quickly achieved at room temperature and in air environment. Another attractive feature of this method is that FeNi/PNG supported on polyamide (PI) film could directly act as electrocatalytic electrode for hydrogen (HER) and oxygen evolution reaction (OER) without the involvement of dispersion and drop-casting of electrocatalyst ink. The FeNi/PNG shows overpotentials of 132 and 353 mV with Tafel slope of 94 and 80 mV dec–1 for HER and OER catalyses, respectively. This simple and convenient method could be extended to other catalytic systems with carbon-based materials as electrocatalysts.