Toluene-sensing Properties of Mixed-potential Type Yttria-stabilized Zirconia-based Gas Sensors Attached with Thin CeO2-added Au Electrodes

Toluene-sensing properties of mixed-potential type yttria-stabilized zirconia (YSZ)-based sensors attached with a thin CeO2-added Au sensing electrode (SE, CeO2 content: 4 - 16 mass%, thickness: 30 - 100 nm), which was fabricated by using a spin-coating method, were examined and the effects of their SE thickness and the additive amount of CeO2 on their toluene response were discussed in this study. The toluene response of the sensors attached with a 16 mass% CeO2-added Au SE increased with an increase in the SE thickness, and the sensor attached with the thickest 16 mass% CeO2-added Au SE showed the largest response, among all the sensors tested. This behavior probably arises from the increase in the number of active sites for electrochemical toluene oxidation in the CeO2-added Au SE.