Tailored bimetallic synergy of iron–cobalt sulfide anchored to S-doped carbonized wood fiber for high-efficiency oxygen evolution reaction

Abstract

Decoupling the scaling relation of intermediates is an effective strategy to improve the oxygen evolution reaction (OER) catalytic efficiency. Herein, S-doped carbon-confined Fe.92Co.08S nanoparticles (Fe.92Co.08S@SC) anchored to S-doped carbonized wood fiber (SCWF) are fabricated via simple synchronous carbonization and sulfidation. Due to the synergistic catalytic effect of bimetallic and the unique structural effect of the supported catalyst, Fe.92Co.08S@SC/SCWF exhibit excellent OER catalytic efficiency with an overpotential of 238 mV at 50 mA cm and stability up to 100 h. Furthermore, a high current density of 500 mA cm−2 at an overpotential of 281 mV was achieved. Theoretical calculations and electrochemical characterizations confirm that bimetallic synergies can accelerate the surface reconstruction of Fe.92Co.08S@SC with highly efficient OER activity. For zinc–air battery applications, Fe.92Co.08S@SC/SCWF exhibits superior power density and stability over commercial RuO2. This work provides insights into the preparation of supported electrocatalysts with bimetallic synergy for high-efficiency OER.