ELECTROCHEMICAL NITROGEN-DIOXIDE GAS SENSOR-BASED ON SOLID POLYMERIC ELECTROLYTE

Gold has been prepared on a solid polymeric electrolyte (SPE) by the c hemical plating method. The characteristics of Au/SPE and the electroc hemical behaviour of the cathodic reduction of nitrogen dioxide on the prepared electrode have been studied in this paper. The loading of Au on SPE increases when the concentration of reductants and the pH incr ease. The maximum roughness factors of Au/Nafion(R) are 340 and 460 wh en hydrazine dihydrochloride and sodium borohydride are used as reduct ants, respectively, for the chemical plating. A linear relationship be tween the limiting current and the concentration of NO2 is obtained an d the sensitivity is 0.33 mu A ppm(-1) when the NO2 concentration is i n the range 20.8 to 104.0 ppm.