A WO₃/Ti₃C₂T_x MXene Composite Sensor for 2-Heptanone Gas Detection at Room Temperature

Area of Science:

• Materials Science
• Chemical Sensing
• Nanotechnology

Background:

• Developing room-temperature gas sensors with high sensitivity for food spoilage volatile organic compounds (VOCs) remains a challenge.
• Tungsten trioxide (WO3) and MXene (Ti3C2Tx) are promising materials for gas sensing applications.
• Composite materials can offer synergistic effects to improve sensor performance.

Purpose of the Study:

• To synthesize and characterize WO3/Ti3C2Tx MXene composite materials.
• To evaluate the gas sensing performance of the fabricated WO3/Ti3C2Tx MXene sensor at room temperature.
• To investigate the underlying mechanisms for enhanced gas sensing properties.

Main Methods:

• In situ growth of WO3 on Ti3C2Tx MXene via a solvothermal method.
• Fabrication of a gas sensor using the synthesized WO3/Ti3C2Tx MXene composite.
• Testing the sensor's response, selectivity, and reproducibility towards 2-heptanone at room temperature (25 °C).

Main Results:

• The WO3/Ti3C2Tx MXene sensor showed a remarkable response of 3.25 to 50 ppm 2-heptanone at room temperature.
• This represents a 2.4-fold enhancement compared to pure WO3 nanosheets (response of 1.34).
• The composite sensor exhibited excellent selectivity and reproducibility for 2-heptanone detection.

Conclusions:

• The hierarchical architecture of WO3/Ti3C2Tx MXene provides a large specific surface area and p-n heterojunction effect, enhancing gas sensing.
• This work establishes a novel strategy for developing advanced room-temperature gas sensing materials.
• The WO3/Ti3C2Tx MXene composite shows great potential for practical applications in food spoilage monitoring.