AMPEROMETRIC SULFUR-DIOXIDE SENSORS USING THE GOLD DEPOSITED GAS-DIFFUSION ELECTRODE

A dispersed catalyst gas-diffusion electrode for SO2 sensors has been developed. The particle size of the catalyst electrode was obtained. A three-electrode potentiostat was used to test the sensing electrode a t an optimal constant potential. When the SO2 diffuses through the por ous electrode, the electrochemical oxidation of SO2 takes place at the active gold sites. The results indicated that the SO2 sensor was stab le and the response time was fast. The sensitivity of the developed SO 2 sensor was 1.002 mu A cm(-2) ppm(-1), and its performance was good.