Comparative study of conventional and inverted P3HT: PCBM organic solar cell

Abstract

This work is a comprehensive comparative study between conventional and inverted bulk hetero-junction (BHJ) Organic Solar Cell (OSC and IOSC) using GPVDM software. Contrary to conventional OSCs with a low work-function cathode located on the top, IOSC is characterized by a bottom transparent conductive oxide cathode. The calculated current-voltage characteristic (J-V) is used to extract the main electrical outputs (figures of merit) of the solar cell: the short circuit current (Jsc), the open circuit voltage (Voc), the fill factor (FF) and the efficiency (η). The effect of a number of physical parameters is studied including thickness of the different layers and materials used as electron (hole) transport layer, ETL (HTL). In addition, different top and bottom electrodes are suggested with mono and multi-thin layer. A comparison between the effect of all these factors in OSC and IOSC is also performed and it was found that IOSC using multi-thin layer ATZ (AZO/TiOx/ZnO) as bottom contact gives the best efficiency of 5.46% in comparison with 5.02% obtained for the conventional OSC with ZnO/TiOx/ZnO contact.