Development of Highly Sensitive and Humidity Independent Room Temeprature NO 2 Gas Sensor Using Two Dimensional Ti 3 C 2 T x Nanosheets and One Dimensional WO 3 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 Ti 3 C 2 T x decorated, WO 3 nanorods based nanocomposite has been investigated. The hydrothermally synthesized WO 3 /Ti 3 C 2 T 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 WO 3 /Ti 3 C 2 T x sensors have been found to be highly selective to NO 2 at room temperature and exhibit much higher sensitivity in comparison to pristine WO 3 nanorods. Furthermore, sodium l-ascorbate treated Ti 3 C 2 T x sheets in WO 3 /Ti 3 C 2 T x enhanced the stability and reversibility of the sensor toward NO 2 even under variable humidity conditions (0-99% relative humidity). This study shows the potential room temperature sensing application of a WO 3 /Ti 3 C 2 T x nanocomposite-based sensor for detecting NO 2 at sub-ppb level. Further, a plausible sensing mechanism based on WO 3 /Ti 3 C 2 T x nanocomposite has been proposed to explain the improved sensing characteristics.