Electrical transport properties of fullerene peapods interacting with light

In this paper, we investigate the transport properties of field-effect transistors (FETs) based on various kinds of fullerene (C-60, C-70, and C-84) peapods. The encapsulation of various fullerenes inside single-walled carbon nanotubes (SWNTs) is characterized by TEM and Raman spectroscopy. Our results indicate that the transport characteristics of p-type SWNTs are extremely sensitive to the encapsulation of various kinds of fullerene. In the absence of light illumination, the threshold voltage of p-type SWNTs shifts towards positive values after C-60 and C-70 encapsulation, and ambipolar transport characteristics are observed for C-84 peapods. The photoinduced electron transfer phenomenon is observed for fullerene peapods under light illumination. The optical response for C-60 and C-70 peapod FET devices is reflected in a shift of threshold voltage towards negative values, and a recoverable characteristic is observed when light is off. After a long period of light illumination, in contrast to p-type C-60 and C-70 peapods, an n-type transport characteristic is observed on C-84 peapods.