Structural and electrical properties of mechanically alloyed ZnO nanoceramic for NTC thermistor application

A simple negative temperature coefficient (NTC) thermistor material ZnO has been synthesized by mechanical alloying. The structural and microstructural properties were investigated by X-ray diffraction and field emission scanning electron microscopy. The electrical properties have been investigated in the temperature and frequency range of 300–500 °C and 100 Hz–1 MHz, respectively. The synthesized sample shows typical NTC behavior in the studied temperature and frequency range. The suitability of the material for thermistor application was analyzed by Steinhart–Hart equations and different thermistor parameters like sensitivity, temperature coefficient of résistance, activation energy and stability factor were calculated. The variation of resistance with temperature follow an exponential behaviour and well matched with Steinhart–Hart equation. It shows the sensitivity ( β ) value of 8079.93 K and the capability of mechanically alloyed zinc oxide for NTC thermistor application.