Non-noble metal coordinated hypercrosslinked polymers based on porphyrin for efficient electrocatalytic OER

Abstract

Electrochemical catalysts for the oxygen evolution reaction (OER) with abundant reserves, high catalytic activity, and robust stability are highly crucial for efficient electrocatalytic water splitting. Herein, we designed and synthesized non-noble metal coordinated porphyrin-based hypercrosslinked polymers (FX-M-TPP), which were characterized by SEM, TEM, and XPS. Their performance as electrocatalysts for OER was evaluated in 1 M KOH, among which FX-FeCo-TPP exhibited a minimum overpotential of 251 mV at 10 mA cm⁻², with a Tafel slope of 35.2 mV dec⁻¹ demonstrating excellent stability. By studying the intermediates in the OER process, it was revealed that the true catalytically active substances are metal hydroxides that evolved from FX-FeCo-TPP. The results of this work provide a new method for designing high-performance OER catalytic materials based on organic compounds.