Structural and electronic properties of zigzag carbon nanotubes filled with smallfullerenes

Abstract

In this work we investigated the encapsulation ofC20 and C30 fullerenes into semiconducting carbon nanotubes to study the possibility of bandgapengineering in such systems. Classical molecular dynamics simulations coupled to tight-bindingcalculations were used to determine the conformational and electronic properties of carbonnanotubes with an increasing fullerene concentration. We have observed thatC20 fullerenes behave similarly to a n-type dopant whileC30 can provide p-type doping in some cases. The combined incorporation of both types offullerenes (hybrid encapsulation) into the same nanotube leads to a behaviour similar tothat found in electronic pn-junctions. These aspects can be exploited in the design ofnanoelectronic devices using semiconducting carbon nanotubes.