In2O3 nanocubes/Ti3C2Tx MXene composites for enhanced methanol gas sensing properties at room temperature

Highly active two-dimensional (2D) nanocomposites, integrating the unique merits of individual components and synergistic effects of composites, have been recently receiving attention for gas sensing. In this work, In2O3 nanocubes/Ti3C2Tx MXene nanocomposites were synthesized using In2O3 nanocubes and layered Ti3C2Tx MXene via a facile hydrothermal self-assembly method. Characterization results indicated that the In2O3 nanocubes with sizes approximately 20-130 nm in width were well dispersed on the surface of layered Ti3C2Tx MXene to form numerous heterostructure interfaces. Based on the synergistic effects of electronic properties and gas-adsorption capabilities, In2O3 nanocubes/Ti3C2Tx MXene nanocomposites exhibited high response (29.6%-5 ppm) and prominent selectivity to methanol at room temperature. Meanwhile, the low detection concentration could be reduced to ppm-level, the response/recovery times are shortened to 6.5/3.5 s, excellent linearity and outstanding repeatability. The strategy of compositing layered MXene with metal oxide semiconductor provides a novel pathway for the future development of room temperature gas sensors.