Analyzing atomic oxygen product evolution in Micro Cavity Plasma Arrays by a combination of a Multi-PMT OES Setup and a 0-D Chemical Model

TL;DR

This study investigates atomic oxygen production in micro-cavity plasma arrays using optical emission spectroscopy and a 0-D chemical model, revealing near-complete oxygen dissociation and providing insights into reactive species generation.

Contribution

It combines a novel multi-PMT OES setup with a simple chemical model to accurately analyze atomic oxygen evolution in micro-cavity plasma arrays.

Findings

Achieved up to 100% oxygen dissociation in plasma.

Developed a multi-PMT system for precise temporal measurements.

Validated experimental results with a 0D chemical model.

Abstract

Dielectric barrier discharges (DBDs) are widely used in applications such as ozone generation and volatile organic compound treatment, where performance can be enhanced through catalyst integration. A fundamental understanding of reactive species generation is essential for advancing these technologies. However, temporally resolving reactive species production, especially during the initial discharges, remains a challenge, despite its importance for controlling production rates and energy efficiency. This study examines atomic oxygen production as a model system for reactive species production in a micro-cavity plasma array, a custom surface DBD confined to micrometer-sized cavities. Optical emission spectroscopy was employed to investigate plasma-chemical processes in helium with 0.1-0.25$\%$ molecular oxygen admixture at atmospheric pressure. The discharge, powered by a 15$\,$kHz, 600$\,$V amplitude triangular voltage, achieved near-complete oxygen dissociation (up to 100$\%$), as determined via helium state-enhanced actinometry (SEA). A novel multi-photomultiplier system enabled precise temporal tracking of atomic oxygen density and dissociation dynamics. To ensure measurement accuracy, a basic 0D chemical model was developed, reinforcing the reliability of the experimental results.