Combustion Growth of NiFe Layered Double Hydroxide for Efficient and Durable Oxygen Evolution Reaction
Yu Zhou, Jinqiang Gao, Min Ju, Yanpeng Chen, Haifeng Yuan, Simeng Li, Jinlong Li, Dongxuan Guo, Mei Hong, Shihe Yang
Abstract
NiFe layered double hydroxide (LDH) with abundant heterostructures represents a state-of-the-art electrocatalyst for the alkaline oxygen evolution reaction (OER). Herein, NiFe LDH/Fe 2 O 3 nanosheet arrays have been fabricated by facile combustion of corrosion-engineered NiFe foam (NFF). The in situ grown, self-supported electrocatalyst exhibited a low overpotential of 248 mV for the OER at 50 mA cm –2, a small Tafel slope of 31 mV dec –1, and excellent durability over 100 h under the industrial benchmarking 500 mA cm –2 current density. A balanced Ni and Fe composition under optimal corrosion and combustion contributed to the desirable electrochemical properties. Comprehensive ex-situ analyses and operando characterizations including Fourier-transformed alternating current voltammetry (FTACV) and in situ Raman demonstrate the beneficial role of modulated interfacial electron transfer, dynamic atomic structural transformation to NiOOH, and the high-valence active metal sites. This study provides a low-cost and easy-to-expand way to synthesize efficient and durable electrocatalysts.