Fabrication and Characterization of Hybrid Solar Cells Based on Perovskite Materials

Perovskite solar cells have gathered great attention in recent years as promising high performance next-generation solar cells with long-term stability at low cost. The aim of this work is to prepare and characterize the perovskite materials, hole transferring materials and electron transferring materials to be used in the fabrication of solar cells. Inverted perovskite solar cells have been fabricated with the following design: fluorine tin oxide (FTO)/electron injection layer/active layer/hole injection layer/metallic upper electrode. MoO₃ and CuI as hole injection materials matched the energy levels with FTO. Different electron injection materials have been investigated to improve the collection of electrons generated namely graphene, graphene oxide and ZnO. ZnO nanoparticles was prepared by sol gel method and used as electron injection layer. Aging the ZnO sol for one month yields a better cell performance due to the formation of nanoridges structure. The nanoridges structure enhanced the surface area of the electron injection layer. Different electrodes were deposited on the cell namely Al, Ag and Au.

The  achievable inverted perovskite solar cell efficiency, fill factor, open circuit voltage and short circuit current density were found to be 2.4%, 0.67, 1.0 V and 0.037 mA/cm², respectively for the following device structure: FTO/ZnO/CH₃NH₂PbI₃/CuI/Au.

 Figure 1. Schematic diagram of the inverted perovskite solar cells