Bottom-up carbon material synthesis from Ni-porphyrin with thermally polymerizable functional groups: Influence of carbon supports and application as CORR electrocatalysts

Abstract

Electrochemical CO2 reduction reaction (eCO2RR) has been widely regarded as a promising approach to address environmental issues associated with rising atmospheric CO2 levels. Recently we have reported a bottom-up synthesis of carbon materials by solid-phase polymerization using functional molecules with thermopolymerizable groups as precursors. Here, by utilizing the technique, ethynyl-functionalized nickel porphyrin was employed as a molecular precursor to synthesize carbon-based catalysts, whose eCO2RR performance was systematically evaluated. Using three different carbon supports, catalysts retaining the Ni-N4 coordination structure were successfully obtained in all cases. Notably, the use of a mesoporous carbon support (CNovel® 010-00) enabled high CO selectivity and suppressed hydrogen evolution over a wide current density range of 10-100 mA cm⁻². These results demonstrate the effectiveness of this strategy for enhancing the electrocatalytic performance of metal porphyrin-based catalysts and highlight its potential for further improvement through precursor design and support optimization.