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arXiv · 2505.08003

Nanosecond and microsecond-pulsed plasma-in-liquid treated copper oxide surfaces

P. Pottkämper·N. Unteregge·S. Weller·A. von Keudell
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Abstract

Nanosecond and microsecond plasma-in liquid systems are explored to oxidize or regenerate a copper oxide surface in situ to serve as a catalyst for electrochemical CO$_2$ conversion. The plasma excitation generates H$_2$O$_2$ in the liquid, which induces the dissolution of Cu into Cu(OH)$_2$ and the recrystallization into Cu$_2$O nanocubes at the interface. The plasma performance of the two excitation schemes is analyzed, showing that the H$_2$O$_2$ production of nanosecond plasma is more efficient than of microsecond plasmas. The nature of the Cu$_2$O nanocubes is evaluated using electron microscopy and electrochemical characterization.

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P. Pottkämper, N. Unteregge, S. Weller, A. von Keudell. 2025-05-12. Nanosecond and microsecond-pulsed plasma-in-liquid treated copper oxide surfaces. https://arxiv.org/abs/2505.08003

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