Encapsulation of floating carbon nanotubes in SiO2

In many applications of carbon nanotubes (CNT), it is desirable to have them embedded in a dielectric such as SiO2, without significantly impacting their electronic properties. Here we investigate the CNT-SiO2 interface of an embedded CNT using first-principles calculations. We show that strong Si-O-C bonds form, suggesting the feasibility of SiO2 deposition on CNTs. We further show that subsequent hydrogenation eliminates all the Si-O-C bonds, leading to floating CNTs with electronic properties very close to those of pristine CNTs in vacuum.