Multiwalled carbon nanotube based aromatic volatile organic compound sensor: sensitivity enhancement through...

Area of Science:

• Materials Science
• Nanotechnology
• Chemical Sensing

Background:

• Growing demand for sensitive, fast, low-power, and stable sensors for aromatic volatile organic compounds (VOCs).
• Benzene and toluene detection is crucial for applications like industrial air monitoring and human breath biosensing.

Purpose of the Study:

• To fabricate and characterize a room-temperature sensor for toluene and benzene.
• To investigate the effect of gold nanoparticle decoration and thiol functionalization on sensor performance.

Main Methods:

• Fabrication of multiwall carbon nanotubes (MWCNTs) decorated with gold nanoparticles (Au-MWCNT).
• Functionalization of Au-MWCNT with 1-hexadecanethiol (HDT) self-assembled monolayer (HDT/Au-MWCNT).
• Characterization using High-Resolution Transmission Electron Microscopy (HRTEM) and Fourier Transform Infrared Spectroscopy (FTIR).

Main Results:

• Successful decoration of MWCNTs with gold nanoparticles and formation of thiol monolayer.
• Detection of benzene and toluene vapors down to the parts per million (ppm) range.
• The HDT/Au-MWCNT sensor exhibited up to 17 times higher sensitivity, enhanced selectivity, and improved response dynamics compared to Au-MWCNT.

Conclusions:

• The developed HDT/Au-MWCNT sensor demonstrates enhanced performance for aromatic VOC detection.
• Self-assembled monolayers significantly improve sensor sensitivity, selectivity, and response dynamics.
• This technology holds promise for advanced air monitoring and biosensing applications.