Carbon nanotube-polymer nanocomposite infrared sensor

Area of Science:

• Materials Science
• Nanotechnology
• Optoelectronics

Background:

• Single-walled carbon nanotubes (SWNTs) exhibit unique electrical properties.
• Infrared photoresponse in SWNTs is influenced by both thermal and photoelectronic effects.
• Improving the photoresponse of SWNTs is crucial for optoelectronic applications.

Purpose of the Study:

• To investigate the enhancement of infrared photoresponse in SWNTs by embedding them in a polymer matrix.
• To differentiate between thermal and photoelectronic contributions to the photoresponse in SWNT-polymer nanocomposites.

Main Methods:

• Fabrication of SWNT-polycarbonate nanocomposites with varying SWNT concentrations (e.g., 5 wt %).
• Measurement of electrical conductivity changes upon infrared illumination in ambient conditions.
• Analysis of the photoresponse to distinguish thermal and photoelectronic effects.

Main Results:

• A significant (4.26%) and sharp infrared photoresponse was observed in a 5 wt % SWNT-polycarbonate nanocomposite at room temperature.
• The photoresponse in SWNT-polymer nanocomposites is dominated by the photoeffect.
• In contrast, pure SWNT films show a photoresponse primarily driven by thermal effects.

Conclusions:

• Embedding SWNTs within an insulating polymer matrix dramatically enhances their infrared photoresponse.
• The polymer matrix facilitates a stronger photoeffect, making SWNT-polymer nanocomposites promising for infrared detection applications.