In light of the successful use of caffeine in perovskite solar cells, a novel nanohybrid system comprised of caffeine packed in a metallic single-walled carbon nanotube is proposed as a viable candidate for organic solar cells. Investigations have been made on the stability of this hybrid system that has a single Cf molecule inside of NT8. In particular, the ideal diameter is found. The investigation’s findings show evidence of a charge transfer between the Cf molecules and the NT8 nanotube, which also attests to the stability of the structure. Electronic and optical computations are used to determine this charge transfer’s location in the Cf @NT8 hybrid system and its direction. The electronic computations and transmission spectra led us to the conclusion that a CT link from caffeine to carbon nanotube is implied by the increased Fermi level position of carbon nanotube after encapsulation.