Thermally activating IrCoP@CNT: A double-phase synergistic catalyst for ultra-efficient acidic oxygen evolution and sustainable Lead electrodeposition

The development of high-performance acidic oxygen evolution reaction (OER) catalysts with ultralow overpotential is crucial for green electrolysis, particularly to address the competitive anodic oxidation between water molecules and Pb²⁺ during lead recovery. In this work, we proposed IrCoP@CNT through an in-situ growth of ZIF-67 on carbon nanotubes (CNTs), controlled phosphidation, and precise deposition of iridium (Ir) species. The superior architecture integrates highly dispersed, nanoscale metallic Ir and crystalline IrP₂ active sites intimately anchored within a three-dimensional conductive network formed by CNTs intertwined with ZIF-derived N, P-codoped carbon, facilitating exceptional charge/mass transport, and enhances structural robustness. Remarkably, IrCoP@CNT achieves an ultralow OER overpotential of 113 mV (10 mA cm⁻²) in 1 M methanesulfonic acid (MSA) at 90 °C, while completely suppressing parasitic Pb²⁺ oxidation to PbO₂. This exceptional selectivity enables near-quantitative lead deposition (99.87 % current efficiency) with record-low energy consumption (420.68 kWh t⁻¹), overcoming the OER/Pb²⁺ oxidation competition. IrCoP@CNT establishes a new paradigm, uniquely merging ultra-high intrinsic OER kinetics with the fundamental elimination of competing anodic side reactions, dramatically minimizing energy dissipation and paving the way for highly efficient and sustainable electrochemical metal recycling.