Room-Temperature Flexible CNT/Fe<sub>2</sub>O<sub>3</sub> Film Sensor for ppb-Level H<sub>2</sub>S Detection
Ding Zhang, Xinguang Huang, Weixue Meng, Junge Yuan, Fengmei Guo, Jie Xu, Yingjiu Zhang, Rui Pang, Yuanyuan Shang, Anyuan Cao
Abstract
Carbon nanotubes (CNTs) had room temperature response, large surface area, and excellent mechanical properties, making them favorable for the design of flexible, wearable, and portable gas sensors. However, CNTs were lacking in response and selective response to different gases, such as H 2 S. Here, we demonstrated a flexible H 2 S ppb-level gas sensor based on a carbon nanotube/amorphous Fe 2 O 3 (CNT/Fe 2 O 3 ) film at room temperature, which was fabricated via a simple one-step solvent-thermal method. The CNT/Fe 2 O 3 film gas sensor exhibited a high selective response to H 2 S (with a response of 55.1% to 100 ppb H 2 S), rapid reversible response at room temperature (with a response time of ∼127 s to 100 ppb H 2 S), and low limit of detection to about 2 ppb. Additionally, the CNT/Fe 2 O 3 film maintained good sensing performance under various bending conditions and could be further fabricated into the fiber gas sensor device via wet stretching, retaining response at the ppb level (with a response of 18.6% to 100 ppb H 2 S). This research on a flexible gas sensor device based on the CNT film/fiber opened up new possibilities for wearable portable electronic device applications.