Enhanced stability of NiFe-layered double hydroxide for anion exchange membrane water electrolysis in half-cell and single-cell long-term testing

Anion exchange membrane water electrolysis (AEMWE) is a promising hydrogen production technology for clean energy storage and conversion applications. However, in practical applications, AEMWE still face various challenges, such as slow reaction kinetics and a poor durability. This study simultaneously performed chronopotentiometry for 672 h in a half-cell (200 mA cm⁻²) and 170 h in a single-cell (500 mA cm⁻²) to comprehensively evaluate the durability of a NiFe-LDH/NF electrode prepared via the hydrothermal deposition of a NiFe-layered double hydroxide (NiFe-LDH) on nickel felt (NF). The half-cell test results showed that after 672 h, the voltage degradation was only 2 mV compared to the initial voltage (1 h). The single-cell test results showed that below 30 h, the cell underwent an activation–stabilisation process, while after 170 h, the voltage degradation was only 45 mV compared to that at 30 h. In situ electrochemical Raman spectroscopy revealed that the formation of Ni(Fe)OOH at high potentials enhanced the oxygen evolution reaction activity of the NiFe-LDH/NF electrode. Meanwhile, TEM and SEM morphological observations showed that the three-dimensional flower-like cluster structure formed by the NiFe-LDH sheets was responsible for the high durability of the NiFe-LDH/NF electrode in both half-cell and single-cell tests.