Research

Professor Walsh’s research focuses on the science and engineering of low-temperature plasmas, with particular emphasis on the design of plasma sources, plasma diagnostics, plasma-liquid interactions and the translation of plasma technologies into practical applications.

His work combines fundamental studies of non-equilibrium plasmas with applied research in areas where plasma can offer new technical solutions. This includes the development of pulsed and atmospheric-pressure plasma sources, optical and electrical diagnostics, and experimental approaches for understanding how plasmas interact with liquids, biological systems and complex materials.

A major strand of his research is concerned with the use of plasma technologies in healthcare, including plasma microbiology, biofilm inactivation, wound-related applications and the development of plasma-based approaches for decontamination and infection control. His work has also extended into agriculture and food systems, including plasma treatment of water, surfaces and biological materials.

More recently, his research has increasingly focused on sustainability, particularly the use of electrically driven plasma processes for water treatment, advanced oxidation and the removal of persistent chemical and biological contaminants. This includes work on plasma-enabled treatment of wastewater and industrial effluents, with the aim of developing lower-carbon alternatives to conventional chemical and energy-intensive treatment processes.

Professor Walsh also has a strong interest in technology translation. He is associated with Plasma Fresh Ltd, a spin-out company developing plasma technologies for real-world deployment in regulated and industrial environments. His wider research programme links plasma physics, electrical engineering, environmental engineering and life sciences, with the goal of moving low-temperature plasma technologies from laboratory systems towards robust, scalable and impactful applications.

Research grants