Positional Controlled Manipulation of the Carbon Nanotube Surface by Selective Screening

Abstract

A scalable process has been demonstrated for the controlled functionalization and positional controlled buckling of multiwalled carbon nanotube (MWCNT) by selectively masking the nanotube surface with chemically inert and thermally stable ceramic material. A uniform thin layer of soluble ceramic precursor, polycarbosilane (PCS), was first coated on MWCNT by the modified solution-based coating technique. The discrete silicon carbide (SiC) islands were then produced on nanotube surface during annealing at high temperature. The size and distribution of SiC islands on the surface of nanotube could be topologically regulated by controlling the thickness of PCS layer on MWCNT. The modulated surface of MWCNTs was then exploited for the site specific functionalization by guiding the incoming functional groups to the exposed surface. By optimizing the openings of the exposed surface of MWCNTs, the degree of chemical modifications could be tailored make. The controlled screening of nanotube surface has also been utilized for the physical modifications like selective buckling of tube walls by impinging high-energy ions on MWCNTs where the position of bending under irradiation fluence could be customized by the degree of passivation of the nanotube surface.