Increasing the Fill Factor and Power Conversion Efficiency of Polymer Photovoltaic Cell Using V₂O₅/CuPc as a Buffer Layer

Abstract

In this study, we investigated the high fill factor (FF) and high power conversion efficiency (PCE) of organic photovoltaic (OPV) cells using a dual hole-transporting layer (HTL) of vanadium oxide (V 2 O 5 )/copper phthalocyanine (CuPc) as a buffer layer. The OPV cell configuration consists of indium tin oxide (ITO)/V 2 O 5 /CuPc/poly(3-hexylthiophene) (P3HT):phenyl C61-butyric acid methylester (PCBM)/LiF/Al. The FF and PCE of the device with a V 2 O 5 /CuPc buffer layer are approximately threefold and tenfold, respectively, greater than those of a conventional device without the buffer layer. The FF and PCE of the device are 62.2 and 2.11%, respectively, under a simulated AM1.5G illumination of 100 mW/cm 2 . The increased PCE and FF of the device are obtained using a V 2 O 5 /CuPc buffer layer, which is attributed to the stepwise hole-transporting configuration and the increased optical absorption from the anode.