Hierarchical NiFe LDH/N-doped Co/Nickel foam as highly active oxygen evolution reaction electrode for anion exchange membrane water electrolysis
Jian‐Sheng Wang, Yongsheng Wang, Xiaoxuan Guo, Mengting Chen, Jinjie Fang, Xiaojie Li, Wei Zhu, Zhongbin Zhuang
Abstract
Anion exchange membrane water electrolyzers (AEMWEs) are emerging as a promising technology due to the high performance and low cost. However, the development of highly active and stable non-precious metal-based catalysts for the anodic oxygen evolution reaction (OER) remains a great challenge. In this study, we present a top-down construction strategy for anode design, resulting in a hierarchical NiFe layered double hydroxide (LDH)/N-doped Co/nickel foam (NF) electrode synthesized via a hydrothermal-gas phase nitridation–electrodeposition method. This electrode features NiFe LDH nanoplates grown on N-doped Co nanowires supported by nickel foam substrates. The NiFe LDH/N-doped Co/NF electrode demonstrates exceptional performance, achieving a current density of 100 mA·cm<sup>−2</sup> at a low overpotential of 262 mV with minimal attenuation of just 7 mV after 100 h of operation. When assembled into an AEMWE, the system requires only 1.63 V to achieve a current density of 1 A·cm<sup>−2</sup>, surpassing the performance of most reported catalysts. The N-doped Co nanowires are shown to enhance both activity and stability by increasing the electrode’s surface area and reinforcing the catalyst–support interaction.