| Title |
Purification of Single-walled Carbon Nanotubes by HCl Treatment and Analysis of the Field Emission Property |
| Authors |
류승철(Seung Chul Lyu); 정다미(Da Mi Jung); 안기태(Ki Tae Ahn); 이한성(Han Sung Lee); 이내성(Nae Sung Lee); 박윤선(Yun Sun Park); 석중현(Jung Hyun Sok) |
| DOI |
https://doi.org/10.3365/KJMM.2010.48.04.335 |
| ISSN |
1738-8228(ISSN), 2288-8241(eISSN) |
| Keywords |
nanostructured materials; purification; electrical properties; activation analysis; carbon nanotube |
| Abstract |
High-quality single-walled carbon nanotubes (SWCNTs) were synthesized by catalytic decomposition of C2H2 using Fe-Mo/MgO catalyst at 800℃. The as-synthesized SWCNTs typically occurred in the form of a bundle with a diameter of 10~20 nm together with amorphous carbon and catalytic impurities, which were removed by a two-step purification process consisting of oxidation and an acid treatment. The oxidation step, using an O2-Ar mixture at 380℃ for 5 hr in a vertical-type furnace and aHNO3 treatment at 100℃ for one hour, was utilized to remove the amorphous carbon particles. Subsequently, metallic catalysts were removed in HCl at room temperature for 5 hr under magnetic stirring. The SWCNT suspension was prepared by dispersing the purified SWCNTs in an aqueous sodium dodecyl benzene sulfonate solution with horn-type sonication. This was then air-sprayed on glass to fabricate CNT field emitters. The samples had a turn-on field value of 4 V/μm and a current density of 0.67 mA/cm2 at 9 V/μm. Increasing the HCl treatment time improved the field emission properties. (Received October 29, 2009) |