α-Fe2O3/TiO2/Ti3C2Tx Nanocomposites for Enhanced Acetone Gas Sensors

Sensors (Basel). 2024 Apr 18;24(8):2604. doi: 10.3390/s24082604.

Abstract

Metal oxide semi-conductors are widely applied in various fields due to their low cost, easy processing, and good compatibility with microelectronic technology. In this study, ternary α-Fe2O3/TiO2/Ti3C2Tx nanocomposites were prepared via simple hydrothermal and annealing treatments. The composition, morphology, and crystal structure of the samples were studied using XPS, SEM, EDS, XRD, and multiple other testing methods. The gas-sensing measurement results suggest that the response value (34.66) of the F/M-3 sensor is 3.5 times higher than the pure α-Fe2O3 sensor (9.78) around 100 ppm acetone at 220°C, with a rapid response and recovery time (10/7 s). Furthermore, the sensors have an ultra-low detection limit (0.1 ppm acetone), excellent selectivity, and long-term stability. The improved sensitivity of the composites is mainly attributed to their excellent metal conductivity, the unique two-dimensional layered structure of Ti3C2Tx, and the heterojunction formed between the nanocomposite materials. This research paves a new route for the preparation of MXene derivatives and metal oxide nanocomposites.

Keywords: Mxene; TiO2; acetone response; gas sensors; α-Fe2O3.

Grants and funding

This work was supported by the Key Research and Development Program of Henan Province (No. 221111220300), the Youth Backbone Teacher Training Program of Henan University of Technology (No. 21420154), the Key Program of National Natural Science Foundation of China (62333013), and the Natural Science Project of Zhengzhou Science and Technology Bureau (21ZZXTCX12).