Molecularly Dispersed Cobalt Phthalocyanine Mediates Selective and Durable CO2 Reduction in a Membrane Flow Cell

High-rate electrochemical CO2-to-CO conversion provides a favorable strategy for carbon neutrality. Molecular catalysts, especially those with isolated metal active centers, are known to be the efficient CO2-to-CO electrocatalysts due to their high selectivity and outstanding instinct activity; however, the controllable scale-up synthesis and durable utilization at industrial current densities still remain a challenge. Here, it is developed a molecularly dispersed cobalt phthalocyanine loaded on carbon nanotube for high-current long-term CO2-to-CO electrolysis. The resultant catalyst exhibits a high CO selectivity with a maximum Faradaic efficiency of 97% and performs a current density of -200 mA cm(-2) in a flow cell with a TOF of 83.9 s(-1), which is among the best of CO-selective electrocatalysts. With a series of impregnation loading experiments, the process of molecular-dispersion or aggregation is investigated. In addition, the application of selective and durable electrolysis at a current of 0.25 A is realized up to 38.5 h in a scale-up MEA configuration. Subsequent characterization shows robust durability closely related to the dispersion of CoPc. This study provides a triumph to catalyze commercial-scale CO production using molecularly dispersed phthalocyanine electrocatalysts.

Automated summary

The study presents a molecular catalyst for high-rate electrochemical CO2-to-CO conversion, exhibiting high CO selectivity at industrial current densities. The developed catalyst shows promising performance with potential for commercial-scale CO production.