Dissolved Carbon Dioxide Sensing with Phenyl-Linked Carbazole Oxazolones in Ionic Liquid and Ethyl Cellulose Moieties

A new optical dissolved carbon dioxide (dCO(2)) sensor based on the spectrofluorimetric signal changes of the fluorescent carbazole derivative in room temperature ionic liquid was proposed. Response of the offered sensor composition to gaseous and dissolved carbon dioxide was tested in ethyl-cellulose-and imidazolium-based ionic liquid moieties. The detection limit was found to be 5 x 10(-7) M [HCO3-] for dCO(2). When embedded in ionic liquid, the employed molecule exhibits excitation wavelength beyond 465 nm, extinction coefficients around 185,000 cm(-1) M-1, and Stokes shifts extending to 56 nm. The ionic liquid-1-ethyl-3-methylimidazolium tetrafluoroborate (EMIMBF4)-provided longer storage time and highly stable microenvironment for the indicator molecule due to the buffering effect. The dissolved carbon dioxide sensor based on dye-doped RTIL does not need extra protection from the ambient air of the lab.