High-Sensitivity Room-Temperature Detection of H2S Using ZnO/Ti3C2TX Nanocomposite: Potential Applications in Exhaled Gas Monitoring

The detection of hydrogen sulfide (H2S) in exhaled breath at room temperature is essential for health monitoring and disease diagnosis. This study investigates a ZnO/Ti3C2TX nanocomposite synthesized by combining ZnO nanoparticles, prepared by a hydrothermal method, with Ti3C2TX MXene. Experimental results demonstrate that the ZnO/Ti3C2TX nanocomposite sensors exhibit excellent H2S detection performance at room temperature with high sensitivity, rapid response time, and robust recovery capability. Specifically, the ZnO/Ti3C2TX-1.0 wt % nanocomposite sensor shows a response of 85.116 at 5 ppm of H2S, which is 14-fold and 35-fold greater than that of pure ZnO and Ti3C2TX MXene, respectively. The sensor exhibits a rapid response (50 s) and recovery time (115 s) at 100 ppb of H2S. Additionally, it shows exceptional sensitivity to H2S 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 H2S levels in healthy and patient breath samples. These findings highlight the potential of the ZnO/Ti3C2TX nanocomposite in exhaled H2S detection at room temperature, offering new insights for developing ultrasensitive biogas sensors.