Controlling plasma chemistry of cold atmospheric-pressure air plasmas

Plasma technologies already form a key part of many of today’s multi-billion pound industries such as the nanoscale fabrication of microprocessors, production of solar cells and the deposition of advanced functional coatings. Underpinning the effectiveness of these essential technologies is the unique non-equilibrium environment created within the plasma; including a mix of reactive neutral particles, ions and energetic electrons. Many applications rely on the synergistic interaction between the mix of species created in the plasma and a sample surface; however one of the fundamental challenges in plasma science is controlling the mixture of reactive plasma species such that they have the desired effect on a target.

Novel cold atmospheric-pressure plasmas can operate into open air, remain at room temperature, and still have the selective desired reactivity characteristics. They have many novel applications ranging from plasma medicine to adhesion enhancement of plastics to green chemistry. As with many plasma applications, key for the effectiveness of these devices is the plasma chemistry, i.e. exactly what mix of reactive species are delivered to a substrate by the plasma.

Many cold atmospheric-pressure plasmas operate in a noble gas such as argon or helium. However, for industrial applications, the cost of these gases can be a problem and plasmas that are generated directly in air are preferred. Unfortunately, the creation of a cold plasma in air is more challenging and the plasma chemistry also increases in complexity. In air-based chemistries reactive species such as OH, NO, O3, O and N play key roles in many applications and are the focus of this project.

This project aims to develop a plasma source in air that can be used for fundamental plasma chemistry studies. The plasma will be characterised using both modelling and experimental approaches. Sophisticated (laser-based) plasma diagnostics and plasma kinetic numerical modelling will enable us to understand the underpinning mechanisms, and importantly also reveal control pathways, e.g. voltage tailoring. With these control strategies, you will develop a proof-of-concept plasma source with a tuneable air chemistry that can be optimised for specific applications in medicine, agriculture and gas conversion.

How to apply:

Applicants should apply via the University’s online application system . Please read the application guidance first so that you understand the various steps in the application process.

Funding:

This is a self-funded project and you will need to have sufficient funds in place (eg from scholarships, personal funds and/or other sources) to cover the tuition fees and living expenses for the duration of the research degree programme. Please check the School of Physics, Engineering and Technology website for details about funding opportunities at York.