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arXiv · 2605.18217

3D CO-TALIF distribution above a micro cavity discharge: A systematic approach for plasma catalysis

Henrik van Impel·Oliver Krettek·David Steuer·Volker Schulz-von der Gathen·Marc Böke·Judith Golda
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Abstract

We investigate a micro cavity plasma array (MCPA) reactor operated at atmospheric pressure, offering excellent diagnostic accessibility and flexible opportunities for catalyst integration. Dissociation processes, such as $\mathrm{CO}$ production from $\mathrm{CO}_{2}$ diluted in helium, are studied. The diagnostic setup, combining TALIF with an ICCD camera, enables three-dimensional spatially resolved measurements of $\mathrm{CO}$ number densities above the $\mathrm{CO}$-generating discharges. The measured distributions are compared to a basic three-dimensional diffusion model, showing good agreement and revealing the dominant transport mechanisms. Flow variation studies indicate that the gas flow inside the reactor follows a laminar, Poiseuille-like profile, while the transport behavior is consistent with literature values for the diffusion coefficient of $\mathrm{CO}$, further validating the model. The high estimated local dissociation within the MCPA discharges (about $40\%$) results in saturation of $\mathrm{CO}$ production under increasing voltage. Combined with complementary diagnostics developed for this discharge, including measurements of surface charges, electric fields, and atomic oxygen, this approach provides a suitable platform for systematic studies of plasma catalyst interactions.

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Henrik van Impel, Oliver Krettek, David Steuer, Volker Schulz-von der Gathen, Marc Böke, Judith Golda. 2026-05-18. 3D CO-TALIF distribution above a micro cavity discharge: A systematic approach for plasma catalysis. https://doi.org/10.1088/1361-6595%2Fae8937

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