CeO^sub 2^-based mixed potential type acetone sensor using MFeO^sub 3^ (M: Bi, La and Sm) sensing electrode

In order to obtain high-performance CeO2-based mixed potential type acetone sensors, MFeO3 (M: Bi, La and Sm) sensing electrode materials were prepared by sol-gel method. The present study mainly focused on the effect of sensing electrode material and sintering temperature on sensing performance of sensors. The results showed that the sensor used BiFeO3-SE sintered at 800 °C presented the best sensing characteristic to acetone at 600 °C, which can detect even 1 ppm acetone with an acceptable response value. The response value (ΔV) of the sensor changed proportionally with the logarithm of acetone concentration at the ranges of 1–5 ppm and 5–200 ppm, and the slopes of which were −7 and −75 mV/decade, respectively. The sensor also showed excellent repeatability, relatively good selectivity, resistance to humidity and good long-term stability. The high-sensing characteristics of the sensor attached with BiFeO3-SE sintered at 800 °C to acetone were explained in terms of morphology and electrocatalytic activity of sensing electrode, which are validated by SEM, BET, XPS, polarization curves and complex impedance.