Phytic acid-decorated Ag/NiCo layered double hydroxide for highly active and durable anion exchange membrane water electrolyzer

Anion exchange membrane water electrolyzer (AEMWE) represents the cleanest and most cost-competitive pathway to generate hydrogen with zero carbon emission. However, the poor activity and durability of oxygen evolution reaction (OER) electrocatalyst in the anode result in the low performance of AEMWE. In this study, we design an electrocatalyst comprising silver nanoparticles anchored in phytic acid-decorated NiCo layered double hydroxide (Ag/NiCo LDH-PA) to address this limitation. The AEMWE equipped with Ag/NiCo LDH-PA anode achieves 1 A cm⁻² and 5 A cm⁻² at ultralow potentials of 1.65 V and 2.04 V, respectively. Additionally, it operates continuously at an industrial current density of 1 A cm⁻² for 650 h. Experimental and theoretical studies reveal that the generated oxygen vacancies and surface-absorbed phosphate ions from phytic acid could efficiently stabilize active sites and reduce the energy barriers of reaction, thereby enhancing the OER performance. These results highlight the importance of surface modification in LDH materials for highly active and durable electrocatalyst development and accelerate the broad deployment of AEMWE.