Using XPS to determine solute solubility in room temperature ionic liquids.
X-Ray Photoelectron Spectroscopy (XPS) was used to quantify the amount of bromide ions present in two samples of [C(4)mpyrr]Br dissolved in the room temperature ionic liquid (RTIL) [C(4)mpyrr][N(Tf)2]. One sample was of a known concentration (0.436 Br atom%); the other was a saturated solution. The results obtained from quantitative XPS analysis indicated that the saturated sample had a concentration, or solubility, of 0.90 Br atom% (746 mM) at 298 K, which was then independently confirmed by potential-step chronoamperometry of the same solution.
Silvester
Debbie S
DS
Physical and Theoretical Chemistry Laboratory, University of Oxford, South Parks Road, Oxford, UKOX1 3QZ.
Broder
Tessa L
TL
Aldous
Leigh
L
Hardacre
Christopher
C
Crossley
Alison
A
Compton
Richard G
RG
D000838:Anions / Q000032:analysis; D001966:Bromine / Q000032:analysis*; D052578:Ionic Liquids / Q000737:chemistry*; D011758:Pyrroles / Q000737:chemistry; D011759:Pyrrolidines; D012995:Solubility; D013057:Spectrum Analysis / Q000379:methods*; D013696:Temperature
C521242:1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)amide; D000838:Anions; D052578:Ionic Liquids; D011758:Pyrroles; D011759:Pyrrolidines; D001966:Bromine