G. Bontempelli et al., ELECTROANALYTICAL SENSORS FOR NONCONDUCTING MEDIA BASED ON ELECTRODESSUPPORTED ON PERFLUORINATED ION-EXCHANGE MEMBRANES, Electroanalysis, 9(6), 1997, pp. 433-443
Electroanalytical sensors, suitable for the analysis and monitoring of
electroactive analytes present in gaseous phase or low-conductive liq
uid media, and based on electrodes in close contact with perfluorinate
d ion-exchange polymers are reviewed. The basic operative mechanism of
these sensors, in which ion-exchange polymers act as solid polymer el
ectrolytes (SPE's), is thoroughly discussed, while stressing the funda
mental reasons why their behavior differs from that of conventional me
mbrane electrodes. The procedures for preparing composite working elec
trodes by coating one side of ion-exchange membranes with stable porou
s films of conductive materials are described, along with the most com
mon strategies followed to assemble this type of sensors. Useful examp
les of measurements in electrolyte-free media of inorganic and organic
electroactive species of interest mainly for environmental analysis a
re given. Future prospects for the development of these sensors are al
so discussed.