Fe‐doped Nickel Carbonate Hydroxide Array Electrocatalysts for Enhanced Oxygen Evolution Reaction

Abstract

Developing efficient and inexpensive oxygen evolution reaction (OER) electrocatalysts is crucial to address the everincreasing energy crisis and environment pollution. In this work, bimetallic nickel-iron carbonate hydroxide arrays were strongly grown on a conductive carbon cloth (NiFeCH/CC) through a facile one-step hydrothermal method, which were used as oxygen evolution reaction (OER) electrocatalysts. Ni 0.8 Fe 0.2 CH/CC requires overpotential of just 246 mV at 10 mA cm À 2 , Tafel slope of 43 mV dec À 1 , and charge transfer resistance of 3.1 Ω for OER in 1 M KOH. The catalyst also shows excellent durability by a long-term operation for 10 h. A post-OER study of Ni 0.8 Fe 0.2 CH/CC reveals that the NiFeOOH species form on the surface during OER and the carbonate ions still intercalate between the cationic layers. Benefiting from a threedimensional structure and Fe doping strategy, the performance of Ni 0.8 Fe 0.2 CH/CC has been improved. This work provides an effective strategy to design efficient OER electrocatalysts in alkaline media.