Enhanced humidity sensing performance of a triple-electrode ionization sensor utilizing carbon nanotubes

This paper introduces a novel ionization humidity sensor featuring a carbon nanotube triple-electrode design, aimed at achieving sensitivities of 381.67 %RH⁻¹ in nitrogen and 11.83 %RH⁻¹ in air, a detection ranges from 25.8 % RH to 100 % RH in nitrogen and 30 % RH to 100 % RH in air, and response times of 11 s and recovery times of 5 s. The sensor leverages the exponential relationship between collecting current and relative humidity, enhanced by the exceptional adsorption properties of CNTs, particularly their large surface area which allows for efficient water molecule attraction, to offer superior performance across diverse detection environments. Two structural configurations are proposed to optimize the sensor's efficiency: one integrating carbon nanotubes directly onto the cathode and another utilizing a silicon strip as a substrate for CNT growth. The design's effectiveness is further validated through simulations that calculate electron distribution, positive ion concentration, and collected current, highlighting the sensor's potential for high-precision humidity detection in real-world applications.