Abstract
A hybrid material, consisting of magnetic iron-oxide nanoparticles (MINPs) and carbon nanotubes (CNTs), abbreviated MCNT, is synthesized by electrostatic interaction between MINPs and the surface of microwave-assisted acidified multi-walled carbon nanotubes (MWCNTs). MINPs uniformly formed and dispersed on the surface of the acidified MWCNTs which were characterized by transmission electron microscopy, X-ray photoelectron spectroscopy, vibrating sample magnetometry, and Raman spectroscopy. The proposed MCNT possessed the advantages of controllable immobilization provided by MINP superparamagnetism and excellent adsorption properties provided by MWCNT large specific surface area. These characteristics made MCNT a preferred gas adsorbent which was evaluated using a gas chromatograph-mass spectrometer equipped with a thermal desorption unit to analyze volatile organic compounds including benzene, toluene, ethyl benzene, xylene, and styrene. Compared to traditional Tenax GR adsorbent, the MCNT adsorbent exhibited lower detection limit and larger breakthrough volume, demonstrating its preferred use as gas adsorbent. © 2009 Elsevier Ltd. All rights reserved.