A novel humidity sensor based on NaTaO3 nanocrystalline

This paper reports the humidity sensitive properties of NaTaO3 nanocrystalline. The NaTaO3 nanocrystalline was synthesized by a simple hydrothermal method, and characterized by X-ray diffraction and scanning electron microscope. Then NaTaO3 humidity sensor was fabricated by coating the nanocrystalline materials on interdigitated electrodes. The device shows good impedance-RH (relative humidity) linearity, narrow hysteresis and rapid time response characteristic. The impedance decreases about three orders of magnitude when the relative humidity (%RH) increases from 33% to 95%RH. The maximum hysteretic value of the sensor is 1%RH and the response time is about 3 s in the operated humidity scope. Moreover, the sensing mechanism was discussed by the complex impedance spectra in detail. These results indicate the potential application of NaTaO3 in humidity sensors.