Sensitivity enhancement of catalytic combustion-type CO gas sensor using an artificial diamond with Pt-loaded CeO₂–ZrO₂–ZnO based catalyst

Abstract

Catalytic combustion-type CO gas sensors employing the mixture of Pt-loaded CeO₂–ZrO₂–ZnO catalyst and artificial diamond with high thermal conductive nature were successfully fabricated. While the sensor employing only Pt-loaded CeO₂–ZrO₂–ZnO catalyst exhibited CO sensing performance over 100°C with high electrical noise, the sensor with the mixture of artificial diamond and the catalyst could operate even at 80°C and the electrical noise was also reduced. At the same operating temperature at 130°C at which both sensors showed the highest sensitivity, the 50% response time toward CO gas concentration change was accelerated from 103 s for the sensor without artificial diamond to 76 s by using the sensor with artificial diamond. Furthermore, the sensitivity toward CO gas was also increased.