Preparation of CdIn2O4 powder by sol–gel method and its Cl2 sensitivity properties

CdIn2O4 powder with the structure of spinel-type was prepared by a sol–gel method in the citric acid system. The structure and the crystal phase of the powder were examined by an X-ray diffractometer (XRD). The shape and size were analyzed by a transmission electron microscope (TEM). Several aspects were surveyed, including effects of calcining temperature on the gas-sensing properties, gas response versus heating voltage, selectivity and long-term stability. The results demonstrated that the CdIn2O4 sensors prepared with the powders calcined at 700 and 800 °C had a high gas response, an excellent selectivity, a quick response behavior, and a good stability to Cl2, compared with the CdIn2O4 sensors thus dealt with at other temperatures.