Room-Temperature Flexible CNT/FeO Film Sensor for ppb-Level HS Detection.

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 HS. Here, we demonstrated a flexible HS ppb-level gas sensor based on a carbon nanotube/amorphous FeO (CNT/FeO) film at room temperature, which was fabricated via a simple one-step solvent-thermal method. The CNT/FeO film gas sensor exhibited a high selective response to HS (with a response of 55.1% to 100 ppb HS), rapid reversible response at room temperature (with a response time of ∼127 s to 100 ppb HS), and low limit of detection to about 2 ppb. Additionally, the CNT/FeO 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 HS). This research on a flexible gas sensor device based on the CNT film/fiber opened up new possibilities for wearable portable electronic device applications.