Tunable volatile organic compounds sensor by using thiolated ligand conjugation on MoS2

Area of Science:

• Materials Science
• Chemical Engineering
• Biomedical Engineering

Background:

• Developing selective gas sensor arrays for breath analysis is crucial for disease diagnosis.
• Volatile organic compounds (VOCs) in breath are key biomarkers for various health conditions, including lung cancer.

Purpose of the Study:

• To engineer a high-performance chemiresistor with tunable sensor responses for VOC detection.
• To functionalize molybdenum disulfide (MoS2) with thiolated ligands to create distinct sensor responses.

Main Methods:

• Conjugating mercaptoundecanoic acid (MUA) to the MoS2 surface to create a functionalized sensing channel.
• Comparing the sensor responses of primitive MoS2 and MUA-conjugated MoS2 to VOCs.
• Evaluating sensor sensitivity down to 1 ppm concentration.

Main Results:

• Primitive and MUA-conjugated MoS2 sensors exhibited distinctly different responses to VOCs.
• MUA-conjugated MoS2 showed negative responses to oxygen-functionalized VOCs, while primitive MoS2 showed positive responses.
• The MoS2 sensors demonstrated high sensitivity to VOCs at concentrations as low as 1 ppm.

Conclusions:

• Ligand conjugation successfully functionalized the MoS2 matrix, enabling tunable sensor responses.
• This approach offers a versatile method for constructing sensor arrays by conjugating various thiolated ligands.
• The developed MoS2 sensors hold promise for real-world applications, such as lung cancer diagnosis via breath analysis.