Constructing AgCoOx with Steering Intermediate Coverage for Efficient Kinetic Promotion of...

The rational design of robust electrocatalysts in view of exceptional stability with fast kinetics toward the oxygen evolution reaction (OER) using a sustainable synthetic strategy is still underway. A simple wet chemical method is established to report Ag- and Co-based oxalate (Ag@CoC₂O₄) for catalyzing OER, which demands 291/241 mV (GC/NF) to reach 10 mA/cm_geo², a reduction of 50 mV compared to CoC₂O₄ with a Tafel slope of 68/60 mV dec^-1, a chronopotentiometry stability of 12/100 h, and a Faradaic efficiency of 98%. The silverization improved the charge transport by reducing the resistance to increase C_dl from 1.02 mF cm^-2, indicating abundant accessible catalytic sites. Further, the catalytic efficiency was manifested by calculating intrinsic and geometric activities. The mechanistic route was analyzed from proton reaction order (ρ_RHE), suggesting a proton-decoupled electron transfer (PDET) process. The kinetic study via operando EIS of Ag@CoC₂O₄ reveals enhanced OER kinetics, less resistance, and more conductivity, suggesting faster kinetics. Further, improved OER activity was strengthened by the Bode study at various potentials. The temperature-dependent analysis inferred that Ag@CoC₂O₄ decreased the activation energy (5.39 kJ/mol) related to CoC₂O₄ (16.32 kJ/mol). Besides, alkaline electrolyzers and solar cell-driven electrolyzers built with a Ag@CoC₂O₄ anode achieve exceptional total water splitting efficiency (1.59 V @ 10 mA/cm_geo²), establishing the suitability for practical applications. The alternative process with a Ag@CoC₂O₄ anode was used to produce zero-carbon green H₂ and was further used for value-added electrocatalysis, thereby showing economic benefits for enhanced water oxidation by exposing surface and bulk active centers for rapid electrolyte diffusion.