Enhancing the photosensitivity of C60 nanorod visible photodetectors by coupling with Cu2O nanocubes
One-dimensional C60 nanostructures with tunable bandgaps and a wide optical absorption range are considered as potential candidates for ultraviolet/visible photodetectors. Herein, we report a low-cost visible photodetector based on C60 nanorods (NRs), which was synthesized using the liquid–liquid interfacial precipitation method. The experimental results demonstrate that the photosensitivity of C60 NR-based visible photodetectors can be enhanced significantly by coupling with Cu2O nanocubes (NCs, ∼20 nm in size). The photosensitivity of a photodetector based on the C60 NR/Cu2O NC is ∼72.5 and 40 fold higher after ratio optimization with 405 and 532 nm light illumination, respectively, which are 3.8 and 5.6 times correspondingly higher than those of pure C60 NRs. Furthermore, the energy band structure of the C60 NR/Cu2O NC heterojunction was analyzed using cyclic voltammetry to illustrate the dramatically enhanced photosensitivity. The enhanced mechanism of photosensitivity is ascribed mainly to the fact that the formation of a p/n heterojunction in the C60 NR/Cu2O hybrid strengthens the separation of photo-induced electrons/holes at the interface.