Cold plasma is a hot topic

The final RSC Belgium lecture event of 2010 was held on Thursday November 18 at the British School of Brussels with Dr. Laurent Denis from the University of Mons. Dr. Denis presented a comprehensive overview of the use of cold plasma technologies - in particular for the application of thin films.

Plasma is a state of matter that makes up in excess of 90% of all matter in the universe. Plasma is essentially a fully ionised gas: the Sun is a ball of plasma. Cold plasma technology has a vast number of applications and is the basis of a multi-billion euro materials industry in Europe.


Dr. Denis (pictured above with section Chairman Prof Bob Crichton) described how cold plasma processes have been developed specifically and purposefully based on their non equilibrium properties and their capabilities to initiate chemical reactions in the gaseous phase at relatively low temperatures (i.e. at room temperature). Although these applications are widespread and involve in many application fields, the main part of Dr. Denis' talk focused on the deposition of thin films where the thickness of the films are between a few micrometres down to a few nanometres.

The majority of the methods described led to material coating applications and the use and performance of these films were illustrated by concrete examples such as self-cleaning windows. Other plasma applications were briefly reviewed ranging from surface functionalisation and etching to sterilisation and medicinal uses.

Examples given by Dr. Denis included coating of orthopaedic prostheses, low-emissivity glass, silicon coating of plastics and a method to enhance dispersion of carbon nanotubes in polymer matrices. The lecture inspired a lively discussion with the audience of over twenty members and friends. The lecture took place in the Swoosh Lounge at BSB and was followed by further discussions over drinks and nibbles.

Current research
Dr. Denis current research is on the study of plasma-enhanced chemical vapour deposition processes to improve the barrier properties of commercial food packaging to oxygen and water at the University of Mons.

He received his PhD from Mons in 2009 with a thesis entitled the 'Influence of the Precursor on the Synthesis Mechanisms of Primary Amine-based Plasma Polymers: From Plasma Diagnostic to Film Chemistry and Applications'. He has also published seven scientific papers as primary author and made twelve contributions to international conferences.