Electrical response of Sm2O3-doped SnO2 to C2H2 and effect of humidity interference

Pure and Sm2O3-doped SnO2 are prepared through a sol–gel method and characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The sensor based on 6 wt% Sm2O3-doped SnO2 displays superior response at an operating temperature of 180 °C, and the response magnitude to 1000 ppm C2H2 can reach 63.8, which is 16.8 times larger than that of pure SnO2. This sensor also shows high sensitivity under various humidity conditions. These results make our product be a good candidate in fabricating C2H2 sensors.