Thermistor elements and temperature sensors are employed for, for example, measuring the temperature of an exhaust gas from an internal combustion engine such as an automotive engine. In such temperature measurement, there is demand for realization of temperature sensing not only at high temperature but also at low temperature, in order to detect temperature sensor failure (wire breakage) in OBD systems (on-board diagnostic systems).
In this regard, Patent Document 1 discloses a sintered electroconductive oxide having a temperature gradient constant (B constant) of about 2,000 to about 3,000 K.