Electrochemical Sensor for Sulfite and Sulfur Dioxide Based on 3-Aminopropyltrimethoxysilane Derived Sol-Gel Composite Electrode

A new sol‐gel derived composite sensor has been developed for the determination of sulfite and sulfur dioxide using 3‐aminopropyltrimethoxysilane, ferrous sulfate and graphite powder by sol‐gel process. Cyclic voltammetry and amperometry studies revealed that the modified iron dispersed sol‐gel derived ceramic composite electrode exhibited excellent characteristics for the electrocatalytic oxidation of sulfite at a reduced potential of +0.35 V with good sensitivity and selectivity. The pH and the potential for sulfite estimation have been optimized. The sensor exhibited rapid and linear response to sulfite in the concentration range from 0.73 mg/L to 95.42 mg/L with a correlation coefficient of 0.997. The proposed sensor can be utilized for the determination sulfur dioxide after absorbing in a suitable medium and has promising characteristics such as, rapid response, good reproducibility and remarkable stability.