High-Sensitivity Room-Temperature Detection of H<sub>2</sub>S Using ZnO/Ti<sub>3</sub>C<sub>2</sub>T<sub>X</sub> Nanocomposite: Potential Applications in Exhaled Gas Monitoring
Yin Liang, Jinfeng Luan, Li Lv, Bin Liu, Wenbin Ren, Xiangqun Chu, Jia Wang, Zheng Lu, Pinhua Zhang, Lulu Du, Guangliang Cui
Abstract
The detection of hydrogen sulfide (H 2 S) in exhaled breath at room temperature is essential for health monitoring and disease diagnosis. This study investigates a ZnO/Ti 3 C 2 T X nanocomposite synthesized by combining ZnO nanoparticles, prepared by a hydrothermal method, with Ti 3 C 2 T X MXene. Experimental results demonstrate that the ZnO/Ti 3 C 2 T X nanocomposite sensors exhibit excellent H 2 S detection performance at room temperature with high sensitivity, rapid response time, and robust recovery capability. Specifically, the ZnO/Ti 3 C 2 T X -1.0 wt % nanocomposite sensor shows a response of 85.116 at 5 ppm of H 2 S, which is 14-fold and 35-fold greater than that of pure ZnO and Ti 3 C 2 T X MXene, respectively. The sensor exhibits a rapid response (50 s) and recovery time (115 s) at 100 ppb of H 2 S. Additionally, it shows exceptional sensitivity to H 2 S at low concentrations, with a detection limit as low as 1 ppb. Based on the excellent sensing performance, oral exhaled gas detection demonstrates that the sensor effectively differentiates H 2 S levels in healthy and patient breath samples. These findings highlight the potential of the ZnO/Ti 3 C 2 T X nanocomposite in exhaled H 2 S detection at room temperature, offering new insights for developing ultrasensitive biogas sensors.