Single-walled carbon nanotubes (SWNTs) have been examined previously as a potential sorbent for volatile organic compound (VOC) sampling. In a recent study, lead author Ms. Jonghwa Oh, graduate research assistant in the department of environmental health sciences and doctoral student in Industrial Hygiene at the University of Alabama at Birmingham, in collaboration with Dr. Claudiu T. Lungu, associate professor in UAB’s department of environmental health sciences, and Dr. Evan L. Floyd, assistant professor at University of Oklahoma, developed a laboratory technique, photothermal desorption (PTD), that achieves pre-analysis desorption by using high-intensity visible light pulses to irradiate the sorbent. PTD can not only increase sensitivity of passive samplers but also abbreviate analytical procedure.
[Photo: Dr. Claudiu T. Lungu (above) and Ms. Jonghwa Oh]
The researchers write that “different fabrication methods of a buckypaper (BP), a self-supporting form of carbon nanotubes (CNTs), were explored; three methods using arc discharge (AD) SWNTs included non-cleaned, acetone-cleaned, and methanol-cleaned and one method using high-pressure carbon monoxide (HiPco) SWNTs. Adsorption efficiencies of the fabricated BPs were compared in terms of Brunauer, Emmett, and Teller (BET) surface area, pore size, and toluene adsorption capacity. All materials were found to have high BET surface area (211 to 649 m2 g−1) and toluene adsorption capacity (25 to 106 mg g−1) but HiPco BP exhibited the highest BET surface area (649 ± 3 m2 g−1) with the smallest mean pore size (7.7 ± 0.3 nm) and the greatest toluene adsorption capacity (106 mg g−1). Additionally, HiPco BP had the simplest fabrication process which taken as a whole is a clear indication that further investigations using the PTD technique should be explored with this material.”
“Fabrication and Adsorption Characterization of Single-walled Carbon Nanotube (SWNT) Buckypaper (BP) for Use in Air Samplers” was published in May in the journal Analytical Methods.