다중벽 탄소나노튜브의 표면처리 방법에 따른 특성비교

Abstract

Functional groups on multi-walled carbon nanotubes (MWNTs) were introduced by UV/ozone treatment, reacting with HNO₃ alone or with H2₂O₄/HNO₃ mixture followed by drying under different conditions. The resulting MWNTs were characterized using a UV-visible spectrometer, SEM, FT-IR, elemental analyzer, and TGA. The amount of oxygen was measured with elemental analyzer and used to check the degree of functionalization on the MWNT surface. Among the various methods tested, the one using H2₂O₄/HNO₃ introduced highest amount of carboxyl groups on the carbon nanotubes, while it damaged the MWNTs. Also, even with the similar amount of functional groups, dispersibility of the functionalized MWNTs in water was differed according to the functionalization method. The carbon nanotubes functionalized by reacting with H₂SO₄/HNO₃ started to degrade at lower temperature than the ones treated by other methods, which was due to the defects introduced during functionalization.