Co, N co-doped porous carbon supported spinel Co3O4 for highly selective electroreduction of CO2 to formate

Ever-increasing energy and environmental problems caused by excessive carbon dioxide have become the bottleneck for energy production and storage, which could be addressed by reducing CO2 to formate electrochemically. Here, a nanocomposite catalyst was developed with spinel Co3O4 supported on Co,N co-doped porous carbon, which was derived from Zn/Co bimetal ZIF (Zeolitic Imidazolate Frameworks) with modulated Zn/Co ratios. The optimized catalyst was obtained with Zn/Co molar ratio of 20 in ZIF and Co3O4 loading amount of 20%, featured with the maximum formate Faradaic efficiency of 84% at -1.0 V (vs. SCE) and current density of 9.23 mA cm-2. The results suggest that the as-prepared electrocatalyst has performed high catalytic activity coupled with excellent selectivity at a lower overpotential and this facile strategy may also provide an alternative route for nano-electrocatalyst fabrication.

Automated summary

A new nanocomposite catalyst has been developed to efficiently reduce carbon dioxide to formate, exhibiting high catalytic activity and excellent selectivity. The optimized catalyst shows the best performance with specific ZIF ratios and loading amounts.