The investigation of synergistic interactions between CO2 plasma and porous catalysts through 2-D fluid modeling

Abstract

The efficiency of plasma-coupled catalysis is believed to be higher than the sum of the efficiencies of the plasma and catalyst when acting independently. However, the underlying microscopic interaction mechanism responsible for this phenomenon remains systematically unexplored. This paper presents an initial demonstration of the combined effects of complex porous-structured catalysts and CO₂ plasma using a two-dimensional fluid dynamics model. The study attests to the contribution of the catalyst’s porous structure in enhancing the electric field intensity, facilitating ‘hotspot’ formation, accelerating plasma development, improving ionization rate, as well as increasing the density of electrons, reactive heavy species, and products. It also uncovers the ability of plasma to penetrate into the surface pores of the catalytic bead, and the potential occurrence of micro-discharges within catalyst interior pores. Meanwhile, the reactive species of plasma such as the energetic electrons and the vibrationally/electronically excited CO₂ in plasma may also impact the surface processes of the catalyst through mechanisms such as reducing reaction barriers. The successful replication of these interactions underscores the potential of this model as a valuable tool for investigating the efficiency optimization of plasma-enhanced catalytic conversion of CO₂.