An excellent impedance-type humidity sensor based on halide perovskite CsPbBr3 nanoparticles for human respiration monitoring

Humidity sensors with fast response, high accuracy and low-power consumption are critical importance in smart home and health monitoring applications. Herein, we demonstrate an excellent impedance relative humidity sensor based on all-inorganic halide perovskite CsPbBr3 nanoparticles (NPs) under low working-voltage (20 mV). The CsPbBr3 NPs humidity sensor exhibits fast response and recovery behavior at room temperature. Moreover, the sensor demonstrates excellent repeatability, low hysteresis and good stability. The humidity sensing mechanism of CsPbBr3 NPs is further studied and discussed by employing an electrochemical impedance spectroscopy measurement. Furthermore, the respiratory monitoring face mask based on CsPbBr3 humidity sensor shows accurate and stable performance, suggesting perovskite CsPbBr3 NPs based humidity sensor have great potential in future real-time health status monitoring applications.