Spark Discharge Plasma-Enabled CO2 Conversion Sustained by a Compact, Energy-Efficient, and Low-Cost Power Supply

Plasma-enabled CO2 conversion is an appealing technology to achieve carbon neutrality. Aiming at cost-effective utilization of CO2, a compact and low-cost commercial power supply was applied to sustain spark discharge plasma-enabled CO2 dissociation under extreme conditions of high vibrational and rotational temperatures and reduced electrical fields. It showed that the power supply could obtain the maximum electrical efficiency of 47.7%. The effects of electrode configuration on the CO2 conversion performance were investigated. The highest CO2 conversion rate of 10.3% and energy efficiency of 8.1% were achieved by 2 and 1 mm needle–plate electrodes, while the highest discharge power of 12.8 W was reached by 6 mm plate–plate electrodes. Collectively, optical emission spectroscopy and computational fluid dynamics simulation revealed the synergistic effects of electron-induced excitation and heat/gas transfer on the conversion performance. This work provides alternatives for plasma power supplies and sheds light on the panorama of spark discharge plasma-enabled CO2 conversion.