Study of the Cesium Carbonate (Cs₂CO₃) Inter Layer Fabricated by Solution Process on P3HT:PCBM Solar Cells

Abstract

In this paper, we studied the effect of the electron injection layer, Cesium carbonate (Cs2CO3), thickness on the performance of organic solar cell (OSC) based on blends of poly (3-hexylthiophene) (P3HT) and [6 Hoppe , H. , Sariciftci , N. S. , & Meissner , D. ( 2002 ). Mol. Cryst. Liq. Cryst. , 385 , 113 .[Taylor & Francis Online] , [Google Scholar],6 Hoppe , H. , Sariciftci , N. S. , & Meissner , D. ( 2002 ). Mol. Cryst. Liq. Cryst. , 385 , 113 .[Taylor & Francis Online] , [Google Scholar]]-phenyl-C61 butyric acid methyl ester fullerene derivative (PCBM). The polymer solar cell consists of molybdenum-oxide (MoO3) as a hole injection layer, P3HT and PCBM bulk hetero junction as an active layer, and Cesium carbonate (Cs2CO3) as an electron injection layer. We measured each device by current-voltage measurement and impedance spectroscopy which is widely used for equivalent circuit analysis of solid state structures. The device with the Cs2CO3 layer showed about 8–10% higher JSC and about 6–8% higher power conversion efficiency compared with the devices without the Cs2CO3 layer.