Flexible solar cells based on CdSe nanobelt/graphene Schottky junctions

Abstract

Flexible solar cells have attracted intense interest since they have potential for the construction of portable and wearable power sources. We fabricated CdSe nanobelt (NB)/graphene Schottky junction flexible solar cells on polyethylene terephthalate (PET) substrates for the first time. The solar cells have an excellent rectification behavior in the dark with a typical on/off current ratio of about 2 × 10⁵. Under air mass (AM) 1.5 global (1.5G) illumination, the solar cells exhibit good photovoltaic (PV) behavior, with a typical open-circuit voltage (V_oc), short-circuit current density (J_sc), and fill factor (FF) of about 0.31 V, 4.73 mA cm⁻², and 36.14%, respectively. The corresponding energy conversion efficiency (η) is about 0.53%. Under bending conditions, the performance of the solar cells does not change obviously. We attribute the satisfactory performance of the flexible solar cells to the ingenious nanomaterials and Schottky junction device structures employed. Our work shows that the semiconductor NBs (NWs) and graphene are promising building blocks for future flexible devices and the CdSe NB/graphene Schottky junction solar cells have potential applications in flexible nano-optoelectronic systems.