Development of Highly Sensitive and Humidity Independent Room Temeprature NO2 Gas Sensor Using Two Dimensional Ti3C2Tx Nanosheets and One Dimensional WO3 Nanorods Nanocomposite

Room temperature gas sensors have been widely explored in gas sensor technology for real-time applications. However, humidity has found to affect the room temperature sensing and the sensor life, necessitating the development of novel sensing materials with high sensitivity and stability under humid conditions at room temperature. In this work, the room temperature sensing performance of a Ti₃C₂T_x decorated, WO₃ nanorods based nanocomposite has been investigated. The hydrothermally synthesized WO₃/Ti₃C₂T_x nanocomposite has been investigated for structural, morphological, and electrical studies using X-ray diffraction, field-emission scanning electron microscopy, transmission electron microscopy, and Brunanuer-Emmett-Teller techniques. The WO₃/Ti₃C₂T_x sensors have been found to be highly selective to NO₂ at room temperature and exhibit much higher sensitivity in comparison to pristine WO₃ nanorods. Furthermore, sodium l-ascorbate treated Ti₃C₂T_x sheets in WO₃/Ti₃C₂T_x enhanced the stability and reversibility of the sensor toward NO₂ even under variable humidity conditions (0-99% relative humidity). This study shows the potential room temperature sensing application of a WO₃/Ti₃C₂T_x nanocomposite-based sensor for detecting NO₂ at sub-ppb level. Further, a plausible sensing mechanism based on WO₃/Ti₃C₂T_x nanocomposite has been proposed to explain the improved sensing characteristics.