CeO2-based mixed potential type acetone sensor using MMnO3 (M: Sr, Ca, La and Sm) sensing electrode

The CeO2-based mixed potential type gas sensors attached with MMnO3 (M: Sr, Ca, La and Sm) sensing electrode have been fabricated to detect acetone. All MMnO3 materials were prepared by a simple sol-gel method. The results indicated that the response of the sensor based on SrMnO3 sintered at 1000 °C to 20 ppm acetone was the highest compared with sensors using MMnO3 (M: Ca, La and Sm)-SE, which was −49 mV. The sensor attached with SrMnO3-SE could detect even 1 ppm acetone, and the response value (ΔV) was −3 mV, which was an acceptable value. The ΔV of the sensor was linearly changed with the logarithm of acetone concentration in the range of 1-50 ppm and the sensitivity was −36 mV/decade. Most notably, the typical 90% response and recovery times of the sensor attached with SrMnO3-SE to 20 ppm acetone were only 2 s and 6 s. Moreover, the sensor manifested good repeatability and stability. Besides, the sensing mechanism of the sensor was explained, and polarization curve was measured to further demonstrate the mixed potential mechanism.