Fabrication and Characterization of a MnO2/Ti3C2Tx Based Gas Sensor for Highly Sensitive and Selective Detection of Lung Cancer Marker Hexanal

MXene, with unique gas-sensing performance and an ultra-high signal-to-noise ratio, is widely used in low -temperature gas sensing. However, the sensitivity, selectivity, and stability of MXene-based and metal oxide semiconductors (MOSs)/MXene-based gas sensors are still inferior. In the present work, MnO2 with a large number of oxygen vacancies and high catalytic activity was introduced on the surface and between the layers of Ti3C2Tx-MXene. Due to the existence of more active centers and p-p heterojunctions, the MnO2/Ti3C2Tx composite-based gas sensor responded 10-20 times higher than the pristine Ti3C2Tx-based sensor to different volatile organic compounds at low temperatures. Furthermore, the composite sensor responded to hexanal (lung cancer marker) in a unique and improved way with good reproducibility and stability. New ideas for designing MXene-based sensors for industrial applications were provided by elucidating the gas-sensing mechanism of the MnO2/Ti3C2Tx composite-based gas sensor.

Automated summary

In this study, MnO2 with high catalytic activity was introduced onto MXene material, improving the sensitivity and selectivity of the gas sensor. The composite material exhibited a 10-20 times higher response to different volatile organic compounds compared to the pristine MXene-based sensor, and showed a unique and stable response to the lung cancer marker hexanal.