Flexible noble-metal-free Fe-based metallic glasses as highly efficient oxygen evolution electrodes

Abstract

Developing low-cost, and efficient oxygen evolution reaction (OER) electrodes with high flexibility is critical for hydrogen production. Here, flexible noble-metal-free Fe-based metallic glassy OER electrodes were fabricated via an electrochemical dealloying method combined with a dipping process. The sample requires a low overpotential of 258 mV to achieve a current density of 10 mA cm⁻² in 1 M KOH solution, and the Tafel slope is 51.7 mV/dec. Galvanostatic test proved the excellent electrochemical stability of the electrodes. The highly efficient performance mainly originated from the high-energy disordered amorphous microstructure combined with the doping effect of nickel. Furthermore, the unique double-layer structure of the nanoporous surface covered with amorphous sheets increased the contact area of the samples. The ductile amorphous matrix together with the amorphous sheets tightly bonded on the nanoporous layer results in high flexibility of the electrodes. Our work provides a simple strategy to fabricate flexible amorphous OER electrodes.