Purification of single-wall carbon nanotubes

With Y-Ni alloy and CaC2-Ni as catalyst, large-scale single-wall carbon nan otubes (SWCNTs) were produced by d.c. arc-discharge method. The yield of SW CNTs and the composition of the raw-soot was quantified with thermogravimet ric analysis (TGA). The burning temperature of SWCNTs in air was also deter mined. On these bases, 350 degrees C was chosen for the first step purifica tion of SWCNTs. Combining with the micro-filtration method, larger than 90% purity of SWCNTs and high purity of carbon nanoparticles were obtained. (C ) 1999 Elsevier Science Ltd. All rights reserved.