Fundamental objectives and applications

The formation of the team dates back to the end of the 1980s when the LPGP became involved in the study of high-power excimer lasers, in particular XeCl (308 nm), under the responsibility of Vincent PUECH, founder of the team and scientific manager until 2008.

Researches were then gradually extended to high power switching (pseudo-sparks), depollution of gaseous effluents (de-NOx and de-VOCs), HF/DF lasers (3-4 µm), treatment of metallic surfaces (cleaning and deposition of thin layers), then the triggering of combustion, the decontamination of surfaces by VUV photons, the biological applications of plasmas (bio-medicine), and more recently the detection or conversion/synthesis of organic molecules, the conception of new materials, in collaboration with academic partners in the frame of projects financed by major French agencies (ANR, ADEME, etc.) and national research programs (Plan Cancer, etc.), the district Région Ile-de-France (Diagplas platform), the CNRS and two thematic scientific groups Labex of Paris-Saclay University. The team was under the responsibility of Stéphane PASQUIERS from 2009 to 2023, and its activities are now coordinated by Joao SANTOS SOUSA.

The physics of rapid pulsed electrical discharges (ns – µs) and the kinetics of plasmas generated by these discharges constitute the basis of the activities of the DIREBIO team: energy deposition in plasmas (in space and time), production and transport of active species, correlation between energy deposition and production of species, reactivity in the gas phase, etc. The team is interested in the physics of these discharges and the kinetics of plasmas produced in gases and mixtures of very varied gases (rare gases and molecular gases).

The discharges studied and developed, or implemented for specific applications, are of different types: micro-discharges, dielectric barrier discharges for “plasma jets” or other reactive species sources, diffuse nanosecond corona discharges, etc. Of an older design, a pre-ionized (photo-triggered) discharge is used for detailed studies of molecular kinetics in gas mixtures.

In recent years, and currently, the team’s main research topics are:

• The kinetics of conversion of hydrocarbons and Volatile Organic Compounds in mixtures of atmospheric gases, in different types of plasma (homogeneous, diffuse, filamentary), with the main application being the reduction of polluting emissions (industry, transport, etc.) and to a lesser extent the triggering of combustion;
• The physics and reactivity of ultra-short (10 ns) pulsed discharges at very high voltage (50 kV and more), which generate a diffuse plasma in air at atmospheric pressure;
• The physics of micro-discharges and “plasma jets”, with application to the development of new materials for electronics, the conversion and synthesis of organic molecules, and bio-medicine;
• The interaction of plasmas with liquids and living matter (cells, microorganisms), particularly for application in oncology;
• The interaction of plasmas with surfaces for the development of mass spectrometry applied to global security, the detection of weakly volatile molecules;
• RF or DC discharge plasmas for the optimization of metal powders as part of work on the additive manufacturing of objects with complex geometry.