Acta Phys. -Chim. Sin. ›› 2010, Vol. 26 ›› Issue (11): 3080-3086.doi: 10.3866/PKU.WHXB20101108

• PHYSICAL CHEMISTRY OF MATERIALS • Previous Articles     Next Articles

Purification of Multiwalled Carbon Nanotubes and Characterization of Their Oxygen-Containing Surface Groups

ZHOU Jin-Mei, LI Hai-Yan, LIN Guo-Dong, ZHANG Hong-Bin   

  1. College of Chemistry and Chemical Engineering, State Key Laboratory of Physical Chemistry for Solid Surfaces, National Engineering Laboratory for Green Chemical Productions of Alcohols-Ethers-Esters, Xiamen University, Xiamen 361005, Fujian Province, P. R. China
  • Received:2010-05-17 Revised:2010-07-24 Published:2010-10-29
  • Contact: ZHANG Hong-Bin E-mail:hbzhang@xmu.edu.cn
  • Supported by:

    The project was supported by the National Key Basic Research Programof China (973) (2009CB939804) and Fujian Provincial Key Scientific & Technical Project, China (2009HZ0002-1).

Abstract:

We conveniently removed the Ni-MgO catalyst components from an as-grown multiwalled carbon nanotube (CNT) using an aqueous HNO3 solution with strong acidity and oxidizability as a purifying reagent. Some oxygen-containing surface groups were generated at the CNT surface, which converted the hydrophobic surface into a hydrophilic surface. The phase composition and the oxygen-containing surface groups of the CNTs treated by nitric acid were determined and characterized using Boehm's neutralizing titration method and X-ray powder diffraction (XRD), temperature-programmed desorption (TPD), Fourier transform infrared (FTIR) spectroscopy, and X-ray photoelectron spectroscopy (XPS) techniques. The results indicated that the total content of the formed oxygen-containing surface groups was the highest for the CNTs treated with 7.0 mol·L-1 aqueous HNO3 at 378 K for 24 h. The content of the three major oxygen-containing surface groups was: carboxyl>lactonic carboxyl>phenolic hydroxyl.

 

Key words: Multiwalled carbon nanotubes, Purification, Oxygen-containing surface group, Surface modification

MSC2000: 

  • O647