Is a catalyst always beneficial in plasma catalysis? Insights from the many physical and chemical interactions

Plasma Catalysis for Hydrogen Production: A Bright Future for Decarbonization

“…The packed bed can be constructed with various bed material geometries, such as pellets, powders, and foams . As shown in Figure , the interactions between plasmas and catalysts are complicated, where catalysts affect the properties of the plasma and vice versa . On one hand, packing materials change the plasma discharge properties, including the creation of microdischarges inside pores larger than the Debye length, propagation of streamers on the surface, modifications in the discharge volume, and enhancement in the electric field.…”

“… 86 As shown in Figure 6 , the interactions between plasmas and catalysts are complicated, where catalysts affect the properties of the plasma and vice versa. 87 On one hand, packing materials change the plasma discharge properties, including the creation of microdischarges inside pores larger than the Debye length, propagation of streamers on the surface, modifications in the discharge volume, and enhancement in the electric field. These effects have a direct impact on the electron energy distribution and rates of electron-impact collisions, consequently leading to changes in the distribution of chemical species within the plasma.…”

“…E-R refers to the Eley–Rideal mechanism, and L-H refers to the Langmuir–Hinshelwood mechanism. Reprinted with permission from ref ( 87 ). Copyright 2023 Elsevier.…”

Unveiling the Mechanism of Plasma-Catalyzed Oxidation of Methane to C2+ Oxygenates over Cu/UiO-66-NH2

“…Due to its nonequilibrium characteristics, nonthermal plasma (NTP) emerges as a promising and attractive alternative for the activation of CH 4 and CO 2 , enabling thermodynamically unfavorable reactions to take place under ambient conditions. , High-energy electrons in the NTP collide with CH 4 and CO 2 , inducing the decomposition of these gas molecules into reactive species, such as free radicals and excited species. − These reactive species can then participate in various reactions, leading to the production of various products. − While extensive research efforts have been dedicated to the plasma-catalytic DRM for the production of syngas, − the direct conversion of CH 4 and CO 2 to oxygenates has received less attention. Recent work by Wang and co-workers demonstrated the substantial production of oxygenates from CH 4 and CO 2 using a water-cooled dielectric barrier discharge (DBD) plasma reactor under ambient conditions. , The use of a Cu/Al 2 O 3 catalyst enhanced the selectivity of acetic acid to 40.2%, while formaldehyde was only produced when using Pt/Al 2 O 3 and Au/Al 2 O 3 .…”

“… 11 , 12 High-energy electrons in the NTP collide with CH 4 and CO 2 , inducing the decomposition of these gas molecules into reactive species, such as free radicals and excited species. 13 − 15 These reactive species can then participate in various reactions, leading to the production of various products. 16 − 18 While extensive research efforts have been dedicated to the plasma-catalytic DRM for the production of syngas, 19 − 21 the direct conversion of CH 4 and CO 2 to oxygenates has received less attention.…”