I&EC 258 |
| Taylor cones are fluid features forming when the meniscus of a conducting liquid is subject to a sufficiently intense electric field. The cone apex then emits a beam of charged particles. This beam consists of metal ions (Purely ionic regime of PIR) in the case of liquid metals, and of charged drops (Pure drop Regime or PDR) for moderately conducting organic electrolytes. Ionic liquids (ILs) may exhibit either of these two limiting regimes, as well as an intermediate or Mixed Regime (MR). The use of Taylor cones of ionic liquids as sources of ions for electrical propulsion has gained increased interest following the realization that the ion beam quality may be very high for certain selected ILs capable of PIR operation. However, little is known to date on either the physics of the ion emission phenomenon, or the reasons why only a few ILs are able to operate in the desired PIR. Theoretical reasons suggest that high surface tension G and high electrical conductivity K are key factors favoring the PIR. In order to test this hypothesis we have measured K and G for a number of ILs recently synthesized by the Kyoto group, involving the EMI cation and anions containing either the cyano group or a metal tetrachloride. Several promising ILs, including EMI-GaCl4, are thus identified, and their ability to run in the PIR is confirmed by time of flight mass spectrometry. |
|
Ionic Liquids: Not Just Solvents Anymore OR Ionic Liquids: Parallel Futures (Sponsored by Green Chemistry and Engineering, Separation Science and Technology and Novel Chemistry with Industrial Applications Sub-Divisions)
8:30 AM-12:30 PM, Wednesday, 29 March 2006 Georgia World Congress Center -- B314, Oral
Division of Industrial and Engineering Chemistry |