The aim of this work is to study the optical and electronic properties of the heterojunction interface between a layer of polymer-sorted semiconducting (6,5) single walled carbon nanotubes (SWNTs) and a layer of titanium dioxide (TiO2). In order to increase the effective interface area for SWNT exciton dissociation, different oxide morphologies have been implemented. On the other hand, in order to address the issue of the electronic coupling at the hybrid interface, solar cells have also been functionalized with a small molecule. This book starts with a theoretical background on the structural and optoelectronic properties of carbon nanotubes as well as on the working principle of different kinds of solar cells. Then, all the procedures and the experimental techniques used for the material processing, the fabrication and the characterization of the SWNT-based hybrid solar cell are described. Finally, the experimental results of the polymer-sorted semiconducting (6,5) SWNT-based hybrid solar cell are discussed, together with some future optimizations that could improve the device performances.