Enhancing Oxygen Evolution Catalysis by Tuning the Electronic Structure of NiFe-Layered Double Hydroxides Through...

Electrocatalytic water splitting is a critical approach for achieving carbon neutrality, playing an essential role in clean energy conversion. However, the slow kinetics of the oxygen evolution reaction (OER) remains a major bottleneck hindering energy conversion efficiency. Although noble metal catalysts (e.g., IrO₂ and RuO₂) show excellent catalytic activity, their high cost and scarcity limit their applicability in large-scale industrial processes. In this study, we introduce a novel electrocatalyst based on selenized NiFe-layered double hydroxides (NiFe-LDHs), synthesized via a simple hydrothermal method. Its key innovation lies in the selenization process, during which Ni atoms lose electrons to form selenides, while selenium (Se) gains electrons. This leads to a significant increase in the concentration of high-valent metal ions, enhances electronic mobility, and improves the structural stability of the catalyst through the formation of Ni-Se bonds. Experimental results show that selenized NiFe-LDHs exhibit excellent electrocatalytic performance in 1 M KOH alkaline solution. In the oxygen evolution reaction (OER), the catalyst achieved an ultra-low overpotential of 286 mV at a current density of 10 mA cm⁻², with a Tafel slope of 63.6 mV dec⁻¹. After 60 h of continuous testing, the catalyst showed almost no degradation, far outperforming conventional catalysts. These results highlight the potential of NiFe-LDH@selenized catalysts in large-scale industrial water electrolysis applications, providing an effective solution for efficient and sustainable clean energy production.