Optimal Path Control for NOx Generation in RF Electric Field with Ionization Generated by Pulsed Discharge

Le résumé fourni par la source

Pulsed discharge plasma, characterized by its rapid voltage rise rate, is capable of generating a large number of high-energy free electrons, giving it fast reaction rates, high reactivity, and mild conditions, thereby holding significant potential for chemical applications, such as nitrogen fixation. However, due to the difference in electron energy required for ionization (13eV) and key path(3.48eV), many side reactions occur in the plasma, which increases energy consumption in the form of heat and light. Meanwhile, independently controlling the abundant generation of free electrons and their energy distribution remains a challenge by using only pulsed discharge. This study proposes a hybrid discharge mode to relatively independently regulate free electrons and their energy distribution, aiming to reduce the energy consumption of NOx production. Through chemical kinetics simulations, it was determined that the key pathway for NOx generation originates from the Zeldovich mechanism involving$\mathrm{N}_{2}(\mathrm{v} \geq 13)$, which produces NO with almost no additional electron energy loss in theory and plays a dominant role under long-term discharge. A detailed experimental study was conducted to investigate the control of free electron density and energy by different pulse repetition rates and radio frequency voltages. The measurement of emission spectra confirmed the effective regulation of vibrational excited states by the RF electric field. Moreover, the RF electric field maintains the density of free electrons, weakens the losses caused by ultra-high energy electrons$(>10 \text{eV})$during the pulse discharge process, and promotes the low-energy production of NO throughout the entire period. Compared to simple pulsed discharge, the NOx energy consumption is effectively reduced with the superposition of the RF electric field.

Ce résumé expose les affirmations des auteurs. BNTIC ne l’interprète pas comme une validation indépendante des résultats.