High-performance ethanol gas sensor achieved by assembling In₂O₃-modified ZnO on multilayered Ti₃C₂T_x MXene

Area of Science:

• Materials Science
• Nanotechnology
• Chemical Engineering

Background:

• Zinc oxide (ZnO) based gas sensors are widely studied but often require high operating temperatures.
• MXene materials, particularly multilayered Ti3C2Tx, offer high surface area and unique electronic properties.
• Indium oxide (In2O3) is known to enhance the performance of semiconductor gas sensors.

Purpose of the Study:

• To develop a novel gas-sensing material with enhanced performance at low temperatures.
• To investigate the synergistic effects of In2O3 modification and Ti3C2Tx MXene support on ZnO.
• To explore the potential of this composite material for sensitive and selective ethanol detection.

Main Methods:

• Synthesis of In2O3-modified ZnO nanoparticles.
• Assembly of the composite material on multilayered Ti3C2Tx MXene.
• Fabrication and characterization of the gas sensor.
• Testing of gas-sensing properties, including response, recovery, selectivity, and stability towards ethanol.

Main Results:

• The composite material exhibited a high specific surface area (160.88 m2g-1).
• Maximum response of 88.90 to 250 ppm ethanol was achieved at a low temperature of 150 °C.
• Fast response/recovery times (5.5/26 s) and a low detection limit (0.5 ppm) were observed.
• Superior selectivity, reproducibility, and long-term stability were demonstrated.

Conclusions:

• The In2O3/ZnO/MXene composite significantly enhances gas-sensing performance compared to bare ZnO.
• The high surface area and 3D heterostructure are key factors for the improved sensing capabilities.
• This work provides valuable insights for designing advanced ZnO-based gas sensors for efficient ethanol monitoring.