V₂C MXene synergistically coupling FeNi LDH nanosheets for boosting oxygen evolution reaction

Oxygen evolution reaction (OER) is a pivotal electrochemical reaction process for many renewable energy technologies. Due to the sluggish OER kinetics, searching for efficient low-cost non-precious metal catalysts is one of the crucial but very challenging steps. Herein, V₂C MXene synergistically coupled with hypophosphite-intercalated FeNi (oxy)hydroxide (H₂PO₂⁻/FeNi-LDH-V₂C) electrocatalyst is synthesized. The H₂PO₂⁻/FeNi-LDH-V₂C exhibits excellent OER performance with an overpotential of 250 mV (η₁₀) and small Tafel slope of 46.5 mV dec⁻¹ in 1.0 M KOH electrolyte, and excellent rechargeable Zn-air battery performance with superior open circuit potential (1.42 eV), power density (137 mW cm⁻²) and well durability. The strong interaction and electronic coupling with prominent charge-transfer between FeNi-LDHs and V₂C MXene endow the composite significant OER performance and structural stability, and the adsorption/desorption balance for the OER reaction pathway, eventually promoting the intrinsic activity. This work demonstrates the great promise of MXene-based nanohybrids as advanced electrocatalysts for renewable energy applications.