MXene/In2O3 nanocomposites for formaldehyde detection at low temperature

As the rapid development of advanced technology and the deterioration of air quality, the application of gas sensors and the research of gas sensitive materials are particularly important. In this paper, MXene/In2O3 nanocomposites were prepared by hydrothermal method. Characterization results showed that the accordion-like MXene became monolayer, and the spherical In2O3 with a diameter of about 200 nm was well combined with uniform size and shape. The formaldehyde sensing test shows that the optimal working temperature of the composite sample (100 °C) is obviously lower than that of the pure In2O3 sample (300 °C), and the response value of the composite to 100 ppm formaldehyde is significantly increased from 66.06 % to 106.8 %. In addition, the composite material has good selectivity, reproducibility, and fast response and recovery speed (1 s/1 s). The gas-sensing mechanism may be related to the synergistic effect of the interface between MXene and In2O3. As a gas detection method at low temperature, the method combining MXene with metal oxide semiconductor has great application potential.