Selective gas sensitivity characterisation based on transition metal doped WS₂ single molecule membrane and its application in lung cancer breath marker detection

Lung cancer is the leading cause of cancer-related deaths worldwide, and innovation in early diagnostic techniques is urgently needed. In recent years, novel sensing technologies based on the detection of volatile organic compounds (VOCs) in exhaled breath have shown great potential in the field of early lung cancer screening due to their advantages of being non-invasive, convenient, and highly sensitive. In this study, the sensing properties of transition metal (Cu, Ag, Pt)-doped WS₂ monolayers for lung cancer-specific VOCs were systematically investigated through the innovative application of density functional theory. The results demonstrate that all three doped systems exhibit excellent thermal stability, and their VOCs adsorption capacity is significantly enhanced compared with that of pristine WS₂. This ensures stable desorption and sensing performance of the material in high-temperature operating environments. Notably, the Ag-WS₂ system performs particularly well in key performance indicators such as charge transfer, bandgap modulation, and recovery time, showing superior adsorption properties for four typical lung cancer biomarkers. More importantly, the Ag-WS₂ system exhibits a unique CO₂-repelling property, which significantly improves detection accuracy. This effectively addresses the common issue of cross-sensitivity interference in traditional methods and provides a theoretical basis for the accurate qualitative analysis of lung cancer-specific VOC mixtures. These research findings not only pave the way for the development of novel early diagnostic techniques for lung cancer but also provide an important scientific reference for preventive lung cancer screening.