In Situ-Polymerized PANI/WS<sub>2</sub> Nanocomposites for Highly Sensitive Flexible Ammonia Gas Sensors and Respiration Monitoring Devices
Zhao Feng, Jiayue Wen, Fanzhou Meng, Ruyu Tian, Shuai Wang, Kaifeng Wang, Yanhong Tian
Abstract
This study reports PANI/WS 2 gas-sensitive sensing materials synthesized with in situ polymerization for high-performance, wearable, flexible gas sensors. The gas sensors were constructed on flexible interdigital electrodes (IDEs) using a drop-coating self-assembly method. Due to the p–n junction structure formed by polyaniline (PANI) and tungsten disulfide (WS 2 ), PANI doped with 2 wt % WS 2 exhibits excellent properties for flexible sensors at room temperature, including high sensitivity, flexibility, and selectivity. The flexible sensor remains sensitive to NH 3 at 100 ppb and maintains a good sensing performance under bending conditions. The mechanism of improved gas-sensitive performance due to p–n junctions has been investigated. In addition to gas sensing applications, a real-time human breath testing device was designed based on a PANI/WS 2 composite membrane, demonstrating its potential application in health assessment.