Development of a rGO-BiVO4 Heterojunction Humidity Sensor with Boosted Performance

Humidity sensors with good repeatability, low hysteresis, and low-power consumption are increasingly important for environmental monitoring and industrial control applications. Herein, an impedance-type humidity sensor under low working voltage (5 mV) utilizing a rGO-BiVO4 nanocomposite is demonstrated. The rGO-BiVO4 humidity sensor exhibits superior sensing performances, including good repeatability, negligible hysteresis (0.47%), fast response and recovery time, low power consumption, good stability, and anti-interference ability. The ultraviolet-visible absorption spectrum reveals that the narrow band gap of the rGO-BiVO4 nanocomposite is conductive to the electron transfer. The complex impedance spectra and the energy band structure analysis further suggest that the boosted humidity performance results from the formation of a heterojunction and the decrease of the heterojunction barrier height. The facile fabrication route, enhanced sensing performance, and excellent device reliability make the rGO-BiVO4 sensor highly attractive for high-end humidity sensing applications.

Automated summary

The impedance-type humidity sensor utilizing rGO-BiVO4 nanocomposite showed superior sensing performances, including excellent repeatability, fast response and recovery time, low power consumption, and anti-interference ability. The enhanced humidity performance is attributed to the formation of a heterojunction and the decrease of the heterojunction barrier height, as revealed by the complex impedance spectra and energy band structure analysis. The rGO-BiVO4 sensor is considered highly attractive for high-end humidity sensing applications due to its facile fabrication route, enhanced sensing performance, and excellent device reliability.