Room-temperature Fabrication of Flexible Polymer Solar Cells

Abstract

Inverted polymer solar cells have been required to use a ZnO as an electron transport layer. Additional annealing process over 120 ̊C is required to form interconnected ZnO nanoparticles(NPs) from sol-gel state for a good film uniformity as well as effective work function modification. However, annealing temperature may induce degradation of flexible substrate such as PET or PEN. To overcome this drawback, PFN has attracted interest due to its unique properties such as an ITO surface modifier and room temperature process. In this study, we demonstrate a dramatic improvement in the PCE of flexible polymer solar cell. This solar cell fabricated on PET shows a short circuit current density(Jsc) of 11.9mA/cm2, an open circuit voltage(VOC) of 0.722V, a fill factor(FF) of 65.9%. In particular, the maximum PCE is 5.68% which is more 25% improved than that of best solar cell using ZnO reported, so far.