AN ELECTROLUMINESCENCE OPTICAL SENSOR SYSTEM BASED ON TIO2 FILM ELECTRODES FOR CONTINUOUS MEASUREMENT OF H2O2 CONCENTRATION IN SOLUTION

Electroluminescence semiconductor optrodes (ELSOs), electrochemical optical sensor systems based on recording the electroluminescence response from semiconductor electrodes, have been proposed for the detection and analysis of chemical species in solution. The possibility of developing an ELSO sensitive to hydrogen peroxide in alkaline solutions has been demonstrated using TiO2 film electrodes. The electroluminescence from this optrode arises under conditions of negative polarization as a result of hole injection in the TiO2 from high-energy OH radicals formed by the electroreduction of H2O2 on the electrode surface. The integrated electroluminescence response as well as a value of the electroluminescence intensity measured immediately after applying the pulsed polarization change linearly on a logarithmic scale when the H2O2 concentration changes in the range 10(-3)-5 x 10(-1) mol 1(-1).