Ce and Co Incorporated Covalent Organic Polymer Based on Tetraethylene Glycol-Linked Porphyrin as a Trifunctional Catalyst for Water Splitting and Zn–Air Batteries

Creating high-efficiency, multifunctional electrocatalysts for the OER/ORR/HER with exceptional performance and durability is crucial for advancing renewable energy technologies. The rapid advancement in portable water-splitting devices has stimulated significant research interest in rechargeable metal-air batteries and solar cells. However, the scarcity of cost-effective, multifunctional electrocatalysts continues to limit their wide application. Herein, we demonstrate a Ce and Co incorporated, tetraethylene glycol-linked tetraphenyl porphyrin-based covalent organic polymer (Ce-Co-TEGP) exhibiting superior and highly productive multifunctional electrocatalytic activity. The catalyst demonstrated excellent performance toward the OER, ORR, and HER. The O binding sites in tetraethylene glycol moieties aid in incorporating Ce into the system. The optimized Ce-Co-TEGP catalyst exhibited superior catalytic activity with low overpotentials (η₁₀) (280 mV for OER and 170 mV for HER). Additionally, the electrocatalyst shows ORR activity with an onset potential of 0.924 V vs RHE and a limiting current density of -5.9 mA cm^-2. The as-synthesized Ce-Co-TEGP catalyst has further exhibited potential as an air-cathode material in rechargeable metal-air batteries. The constructed device exhibited superior open-circuit voltage, increased capacity, and peak power density, along with outstanding discharge-charge performance and extended cycle life.