Applied Spectroscopy · 1994 · 18 citations · 8 references
Natural SciencesChemistryEnvironmental SciencesAnalytical ChemistryElectrochemistryEnvironmental ChemistryElectroanalytical ChemistryElectrochemical DetectionElectrochemical SensorsEnvironmental AnalysisEnvironmental Analytical ChemistryRaman SpectroscopyAnalytical Detection Of Organic PollutantsChlorinated HydrocarbonsChlorinated SolventsElectrochemical Environmental SensingElectrochemical MeasurementsRemote Sensing For DetectionSensing In Aqueous MediaSurface-enhanced Raman Scattering
An in situ method for the determination of trichloroethylene (TCE), perchloroethylene (PCE), chloroform (CHCl 3 ), and carbon tetrachloride (CCl 4 ) in aqueous solution is described. The method is based on ESERS—a combination of electrochemical methods and surface-enhanced Raman scattering (SERS). Electrochemistry prepares the surface of a copper electrode for SERS and concentrates the analyte on the surface. The formation of common reaction products for chloroalkanes and for chloroalkenes prevents unequivocal differentiation within a specific class of chlorinated hydrocarbons. However, spectroscopic selectivity between the chloroalkane and chloroalkene classes is excellent, while differences in electrochemical response provide a secondary means for differentiating analyte class. Sensitivity was found to be: <1 ppm for TCE; 15 ppm for PCE; 15 ppm for CHCl 3 ; and 10 ppm for CCl 4 . Application of the method to groundwater contaminated with TCE has been demonstrated. In combination with a fiber-optic waveguide, the ESERS technique offers potential for remote detection of chlorinated hydrocarbons in groundwater and remediation process streams.
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