Insights into non-thermal plasma chemistry of acetone diluted in N₂/O₂ mixtures: a real-time MS experiment

Abstract

Understanding non-thermal plasma reactivity is a complicated task as many reactions take place due to a large energy spectrum. In this work, we used a well-defined photo-triggered non-filamentous discharge to...

Monitoring of n-hexane degradation in a plasma reactor by chemical ionization mass spectrometry

“…H 3 O + precursor ion does not react with NO 2 or NO. Consequently, the NO 2 + or NO + ions observed with the H 3 O + precursor ion come from fragmentations, as observed by Thomas et al 33 For example, the reaction of H 3 O + ion with N 2 O 5 produces NO 2 + ions. The mixing ratios measured for NO and NO 2 (ESI Table 1†) are global values for all the neutrals whose reactions with H 3 O + yield NO + and NO 2 + respectively.…”

“…30 It is a very sensitive technique for the real time analysis of VOCs and has applications in many areas: atmospheric research, food analysis, heath monitoring. 31,32 Only in a few cases PTR-MS instruments have been applied to the determination of plasma degradation products: results are available for acetone, 8,33 toluene, 3 2-heptanone, 34 ethyl acetate. 35 The precursor ions used in all these studies are H 3 O + ions, since they are quite efficient in detecting the target VOCs and most of their degradation products, and only in the case of acetone, O 2 + ions were also used to detect alkane degradation products.…”

Ultrafast and Reversible Superwettability Switching of 3D Graphene Foams via Solvent-Exclusive Plasma Treatments

“…In controlling the surficial wettability of the 3D GFs, the generation of solvent-exclusive plasmas with Joule heating (>2600 °C) is of importance upon microwave irradiation. For superhydrophilic-to-superhydrophobic transition (water contact angle (WCA) = ∼168°), acetone vaporization was combined with ultrashort microwave irradiation (≤5 s) to induce the plasma-mediated generation of nonpolar methyl radicals and their subsequent chemisorption on graphene by Joule heating. , Next, to induce superhydrophilic transition (0°), water vapors were used to generate microwave-assisted plasmas (≤10 s), allowing polar hydroxyl radicals to be covalently dangled on the surficial hotspots. Unlike ultrathin 2D graphene, the 3D GFs readily permit deep microwave penetration with minimum energy loss; , as arc discharge is produced only within 1–2 s, the radical chemisorption can be completed within a few seconds.…”