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arXiv · 2504.12906

Water activation using Ar-H$_2$ atmospheric pressure plasma jets

Fellype do Nascimento·Ananias Alves Barbosa·Konstantin Georgiev Kostov
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Abstract

Whether for materials processing or medical applications, the use of atmospheric pressure plasma jets (APPJs) has emerged as a relevant alternative to conventional methods. Within the APPJs research field, the search for innovation aims not only to solve existing problems but also to explore novel options for generating plasma jets and find new possible applications. In this work, the properties of Ar-H$_2$ APPJs generated using two plasma sources that differ in the frequency, amplitude, and waveform of the generated voltage signal were studied through electrical, thermal, and optical characterization. The discharge parameters were analyzed as a function of the H$_2$ content in the gas mixture, with this parameter varying from 0\% to 3.5\%. Optical emission spectroscopy revealed that the same reactive species were produced for both plasma sources, except nitric oxide (NO), which was observed only for the source operated at a higher frequency (PS #1). Applications for water activation were performed without H$_2$ and with 3.5% H$_2$ in the gas mixture. The results of water treatment revealed that ammonia is also produced when H$_2$ is added to the working gas. This finding suggests that the water treated by a Ar-H$_2$ plasma jet can be an attractive option for use in agriculture.

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Fellype do Nascimento, Ananias Alves Barbosa, Konstantin Georgiev Kostov. 2025-12-19. Water activation using Ar-H$_2$ atmospheric pressure plasma jets. https://doi.org/10.1016/j.vacuum.2025.115027

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