Modeling of titania nanoparticle accumulation at the open end of single-walled carbon nanotubes prior to TiO2 encapsulation

Abstract

Carbon nanotubes (CNTs) and titanium dioxide (TiO2) are perhaps the most well-known nanoparticles. The encapsulation of TiO2 into CNT could provide ideas for the development of targeted drug delivery systems. It is intuitively understood that due to particle size limitation, the relatively large size of TiO2 prevents its encapsulation into CNT. However, it could be possible for TiO2 to encapsulate when those two types of particles are still of comparable size. Motivated by experimental results, the aim of this paper is to utilize the Lennard-Jones (6-12) potential function and applied mathematical modeling tools to understand why TiO2 nanoparticles aggregate at only one side of the carbon nanotube in order to be encapsulated into the tube (which is part of the main problem surrounding the encapsulation of TiO2 nanoparticles into SWNT). The theoretical prediction suggests that TiO2 particles are likely to cluster together since the energy level between two TiO2 molecules and a carbon nanotube is lower than that between a TiO2 molecule and a carbon nanotube. This work could be considered as one of the first step models to be used with the analytic approach before developing more complicate ones. Copyright © 2010 American Scientific Publishers All rights reserved.