Sensing performance of α-Fe2O3/Ti3C2Tx MXene nanocomposites to NH3 at room temperature

Abstract

Room temperature (RT) gas sensors play a crucial role in the development of wearable and portable devices. Herein, a single hydrothermal approach was used to effectively rivet the α-Fe2O3 to the functionalized Ti3C2Tx MXene plates to prepare the α-Fe2O3/Ti3C2Tx MXene composites material with high specific surface area (29.2 m2/g) and abundant functional groups, forming a hybrid heterojunction structure. A side-heated sensor was manufactured and its sensing performance for a variety of vapors were measured experimentally. The morphology and crystal phase of the composite products were analyzed through a range of testing technique. The rose-like α-Fe2O3/Ti3C2Tx MXene sensor revealed a response value and rapid response/recovery times of 18.3% and below 2.5 s for 5 ppm NH3 gas at RT under relatively humidity (RH) of 22%. Meanwhile, it illustrated an excellent linear response in the vary of 5–100 ppm, excellent reversibility and the long-term stability. In addition, a plausible mechanism of the α-Fe2O3/Ti3C2Tx MXene sensor was predicted, and the adsorption capacity of composites material was confirmed by the support of density functional theory (DFT) calculations. This work is expected to provide a fresh idea for the design of other high properties RT gas sensors in the future.