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Abstract The electron-induced secondary electron emission (SEE) yields of imidazolium-based ionic liquids are presented for primary electron beam energies between 30 and 1000 eV. These results are important for understanding plasma synthesis of nanoparticles in plasma discharges with an ionic liquid electrode. Due to their low vapor pressure and high conductivity, ionic liquids can produce metal nanoparticles in low-pressure plasmas through reduction of dissolved metal salts. In this work, the low vapor pressure of ionic liquids is exploited to directly measure SEE yields by bombarding the liquid with electrons and measuring the resulting currents. The ionic liquids studied are [BMIM][Ac], [EMIM][Ac], and [BMIM][BF4]. The SEE yields vary significantly over the energy range, with maximum yields of around 2 at 200 eV for [BMIM][Ac] and [EMIM][Ac], and 1.8 at 250 eV for [BMIM][BF4]. Molecular orbital calculations indicate that the acetate anion is the likely electron donor for [BMIM][Ac] and [EMIM][Ac], while in [BMIM][BF4], the electrons likely originate from the [BMIM]+cation. The differences in SEE yields are attributed to varying ionization potentials and molecular structures of the ionic liquids. These findings are essential for accurate modeling of plasma discharges and understanding SEE mechanisms in ionic liquids.
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Understanding the important variables to optimize glycolysis of polyethylene terephthalate with lanthanide-containing ionic liquids
Lanthanide metal ionic liquids (MILs) are tunable catalysts for the glycolysis of poly(ethylene terephthalate). Enhanced cooperativity with high ionic liquid : metal salt ratios lowers the required metal content to increase catalyst sustainability.
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- Award ID(s):
- 1757942
- PAR ID:
- 10475839
- Publisher / Repository:
- RSC
- Date Published:
- Journal Name:
- RSC Sustainability
- Volume:
- 1
- Issue:
- 4
- ISSN:
- 2753-8125
- Page Range / eLocation ID:
- 938 to 947
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/d3su00090g
