Low-Power Tunable Micro-Plasma Device for Efficient and Scalable CO₂ Valorization

Valorizing CO₂ into chemical building blocks via efficient electrified processes could significantly decrease carbon emissions. In this work, a device that allows generation of tunable micro-plasma modes (arc, pulsed, pulsed arc) on a chip for efficient, low-power and renewable chemical production is presented. This concept is first demonstrated by using nanosecond repetitively pulsed (NRP) micro-plasma for pure CO₂ splitting and show that the pulse micro-plasma maintains a peak energy efficiency of 29% across 0.2%-21% CO₂ conversion at plasma powers below 1 W-nearly an order of magnitude lower power than other systems with comparable performance. The kinetic studies feature pulsed arc mode as a novel way to improve CO₂ conversion, where CO production tripled compared to pulsed mode with negligible energy efficiency losses. In addition, these devices are also capable of performing dry reforming of methane (DRM) with a maximum energy efficiency of 33% and a syngas ratio close 1. The fact that these devices are low-power, versatile and built as chips enables scalable, sustainable and decentralized CO₂ conversion.