Room-Temperature Ammonia Gas Sensor Based on Ti3C2Tx MXene/Graphene Oxide/CuO/ZnO Nanocomposite

Two-dimensional(2D) Ti(3)C(2)Tx Mxene has currentlydemonstrated significant potential for gas sensing application witha high signal-to-noise ratio at room temperature. Herein, we presentthe mixture of popular NH3 sensing materials such as grapheneoxide (GO), copper oxide (CuO), and zinc oxide (ZnO) into Ti(3)C(2)Tx Mxene to be a high-performance NH3 gassensor at room temperature. Various nanocomposites such as Mxene/GO,Mxene/ZnO, Mxene/CuO, Mxene/GO/ZnO, Mxene/GO/CuO, Mxene/ZnO/CuO, andMxene/GO/ZnO/CuO were synthesized via the hydrothermal method andused as NH3 sensing materials in room-temperature gas sensors.The Ti(3)C(2)Tx MXene/GO/CuO/ZnO nanocomposite gassensor exhibited the best NH3 gas sensor. The effects onthe weight ratios of Ti(3)C(2)Tx MXene/GO/CuO/ZnOwere also investigated, and the optimal Ti(3)C(2)Tx MXene/GO/CuO/ZnO weight ratio was determined to be 9:1:5:5. Theoptimal Ti(3)C(2)Tx MXene/GO/CuO/ZnO based gas sensorshowed a high response of 96% at 200 ppm of NH3, humidityindependence in the range of 30-70%RH, good linear relationship(R (2) = 0.998), low limit of detection of4.1 ppm, and high selectivity to NH3 over several gases/VOCsincluding formaldehyde, ethanol, methanol, isopropanol, toluene, andacetone. The NH3-sensing mechanism was proposed based onthe modulation of complex p-n heterojunctions via the electronaccumulation layer in the n-type of GO/CuO/ZnO and the electron depletionlayer in the p-type Ti(3)C(2)Tx Mxene.

Automated summary

Two-dimensional Ti(3)C(2)Tx Mxene has shown potential for gas sensing application at room temperature. In this study, popular NH3 sensing materials, such as graphene oxide (GO), copper oxide (CuO), and zinc oxide (ZnO), were mixed into Ti(3)C(2)Tx Mxene to create a high-performance NH3 gas sensor. Various nanocomposites were synthesized and used as NH3 sensing materials in room-temperature gas sensors. The Ti(3)C(2)Tx MXene/GO/CuO/ZnO nanocomposite gas sensor showed the best performance for NH3 sensing.