Electrochemical hydrogen and oxygen evolution reactions from a cobalt-porphyrin-based covalent organic polymer.

Covalent organic polymers have attracted much attention due to their high specific surface area, superlative porosity, and diversity in electronic structure. Herein, a novel porous cobalt-porphyrin-based covalent organic polymer (CoCOP) is fabricated through the Schiff-base condensation reaction, which is used as a difunctional electrocatalyst for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). The CoCOP possesses a high surface area and strong synergistic effect between the cobalt-porphyrins and the CN groups, resulting in efficient HER and OER performances. The CoCOP required relatively low overpotentials for both HER (121 mV to reach 1.0 mA cm-2 and 310 mV to reach 10 mA cm-2) and OER (166 mV to reach 1.0 mA cm-2 and 350 mV to reach 10 mA cm-2) in alkaline media. This work may provide a new idea for the design of non-noble metal-based coordination polymers with excellent structure and high electrocatalytic performance.