Oxygen atom activated ZIF-67/carbon cloth in plasma system for CO2 reduction.

ZIF-67 was grown in situ on carbon cloth (CC) using a simple one-step method. The prepared ZIF-67/CC electrodes exhibited excellent CO2 reduction reaction (CO2RR) performance in a dielectric barrier discharge plasma reactor. The highest concentrations of produced formic acid and formaldehyde were 9.16 and 0.068 mmol L-1 at a reaction time of 1 h, respectively. The high performance is related to the unique high aspect ratio structure and pad-like cavity of ZIF-67, which results not only in an increase in the specific surface area for CO2 adsorption but also in the hydrophobicity of the electrode. Unexpectedly, the superoxide radical (·O2-) greatly affects the reduction performance of the electrode. In addition, the ZIF-67/CC electrode maintained good CO2RR performance in the presence of different pollutants, and the production of formic acid and formaldehyde increased to 10.81 and 0.11 mmol L-1 at 1 h with the addition of 10 mg L-1 phenol. This research provides new directions in the field of plasma catalysis.