In an effort to curb climate change, targets to reduce greenhouse gas emissions are imposed by governments around the work. Mineral, chemical, refining, iron and steel industries contribute significantly to the total anthropogenic CO₂ emissions. Strategies to achieve emissions reductions include green electricity, electrifying heating and industrial plasmas. Plasmas have a key role to play in this.

The nonequilibrium distribution of energy in nonthermal plasma provides unique opportunities for energy and gas conversion. Molecules that require high temperature and/or pressure to activate by thermochemical processes, like CH₄, CO₂, or N₂, can be activated in nonthermal plasma by excitation or dissociation through collisions with high energy electrons. As a result, nonthermal plasma offers an electrically driven, near-ambient temperature and pressure method for chemical conversion for energy storage applications.

Work in our group has focused on elucidating pathways for plasma-driven production of CH₃OH or NH₃, two potential molecules for energy storage, from CH₄ and O₂ or N₂ and H₂, respectively. These transformations occur through a series of physical and chemical processes that occur in nonthermal plasma and (possibly) on catalytic surfaces. Understanding the species and reactions that drive chemical conversion is enabled by use of molecular beam mass spectrometry or various optical diagnostic techniques available in our lab.

Further readings:

J. Jiang and P. Bruggeman. “Investigation of the Mechanisms Underpinning Plasma-Catalyst Interaction for the Conversion of Methane to Oxygenates” Plasma Chemistry and Plasma Processing (2022) 42:689–707 https://doi.org/10.1007/s11090-022-10251-5

B. Bayer, P. Bruggeman, and A. Bhan. “Species, Pathways, and Timescales for NH₃ Formation by Low-Temperature Atmospheric Pressure Plasma Catalysis” ACS Catalysis (2023) 13, XXX, 2619–2630 https://doi.org/10.1021/acscatal.2c05492