Intrinsically Flexible CNT-TiO2-Interlaced Film for NO Sensing at Room Temperature

• The CNT/a-TiO 2 sensors exhibit high sensitivity of 41% to 50 ppm NO at room temperature. • The CNT/a-TiO 2 sensors achieve fast-stable-reversible response/recovery under UV irradiation. • A novel alternating structure consisting of flexible CNT segments and rigid CNT/a-TiO 2 segments shows intrinsic flexibility. Carbon nanotubes (CNTs) are potential candidates for wearable gas monitoring devices based on their large surface area, room temperature response and flexibility. Considering the demand on sensitivity and flexibility, innovated structural design is essential for realizing those applications. Here, we present a carbon nanotubes-anatase titanium dioxide (CNT/a-TiO 2 ) film-based sensor by in situ hydrolysis and calcination. The CNT/a-TiO 2 sensor exhibits good sensitivity (41% resistance change in response to 50 ppm NO), fast and reversible response at room temperature, and high selectivity toward NO among several toxic gases including NH 3 , NO 2 , CH 4 and H 2 S. Furthermore, the continuous CNT/a-TiO 2 network, consisting of numerous flexible micro-areas of CNT segments interlaced with rigid CNT/a-TiO 2 active segments, can endure complex deformations while maintaining their superior sensing properties. These lightweight CNT/a-TiO 2 films with high performance and intrinsic flexibility films have application potential in future wearable electronics and gas monitoring devices.