Dynamic of the research subjects and directions and the most important achievements  are the following:

 

1. Development of plasma sources

Innovative types of atmospheric pressure, cold (nonthermal) plasma jet sources operating in various gases for applications in nanotechnology, biomedicine, environment, fusion technology.

• High power RF plasma jet (torch)
• Low power RF plasma jet
• Axial DBD plasma jet
• Planar DBD plasma jet

Low pressure discharges and equipaments:

• Low pressure RF plasma jet
• Plasma sources for PECVD
• Plasma treatement sources
• Magnetron sputtering sources
• Inside gap plasma generators

 

2. Plasma synthesis of nanomaterials, process development characterization

Processes and equipaments suitable for syntesis of:

• Carbon nanowalls (CNW)
• Carbon nanofibers
• Core-shell metal nanoparticles coated with graphite layers
• Nano and microparticles
• Composite materials (metal particles in carbon matrix, metal particles in polymer layers)

 

3. Plasma Processing: Materials and Fusion Technology

In the field of surface modification, we have proved that the atmospheric pressure plasma sources developed for functioning at low RF powers, both in DBE and DBD discharge configurations, are capable of increasing wettability (contact angle measurements) of polymeric materials (2 ISI papers), including the case of Teflon, and may promote the cell adhesion on the treated surfaces (Partnership, Ideas contracts, 1 PhD thesis defended, 1 PhD thesis in course).

• Polymer modification for wettability control
• Deposition of thin polymeric films
• Thin films and multilayers by Magnetron Sputtering, PECVD and combined MS-PECVD
• Cleaning of surfaces at atmospheric pressure
• Plasma in liquids

 

 

4. Processes in plasmas and their diagnostics

For the development of plasma sources and configurations, as well as for the understanding of the processes responsible for the material synthesis or surface modification, plasma diagnostics was essential. Such as, the operation of RF plasma jets in DBE configuration has been investigated by imagistic, optical emission spectroscopy and electrical measurements. Similar measurements have been implemented for DBD RF plasmas, which, in conjunction with simulation of OES spectra (collaboration with University of Bucharest, Physics Faculty) provided valuable information regarding the operation regimes.
A complete diagnostics of the low pressure expanding RF plasma generated in argon and injected with acetylene and hydrogen during carbon nanowalls synthesis has been performed. The results, correlated to those devoted to material characterization, pointed out toward the existence of an optimal distance from the injection point, in which the maximum of high mass ionic species densities were determined, but still enough hydrogen is present.
In the topic related to plasma polymerization, mass spectrometry and OES allowed the determination of main species present in plasma and the existence of polymerization reaction in plasma volume, which lead to formation of large mass oligomers.
Important achievements were obtained regarding the OES monitoring of the sequential process of metal-carbon nanocomposites synthesis, which offered information on the process stability and reproducibility during deposition of mixed layers with controlled ratio of metal to carbon.

• Optical Emission Spectroscopy
• Mass Spectrometry
• Langmuir Probe measurements
• Imaging

B. Mitu, XVth CPPA, Iasi, Romania, July 2010