Imaging organic solar cell morphology with organic light emitting diode-organic solar cell devices

摘要

Organic solar cell (OSC)-organic light emitting Diode (OLED) stacked structures are investigated for their use inimaging the morphology of the bulk heterojunction layer used in OSCs. In lieu of the top cathode, bilayer OLEDdevices can be deposited directly on top of the otherwise traditional OSC device. Design considerations and deviceoptimization are detailed. Results show that the bulk heterojunction layer composed of a blend of poly(3-hexylthiophene) (P3HT) and phenyl-C61-butyric acid methyl ester (PCBM) is sufficiently hole-conductive to allow forreasonably strong emission, peaking at a brightness of 175 cd/msup2/sup at a driving voltage of 8.5V and a current density of12.5mA/cmsup2/sup. Since the OLED is in intimate contact with the P3HT:PCBM layer, it provides enhanced images of thebulk heterojunction with information on macro-scale defects and morphological variations. By tuning the emissionintensity, detailed images can be obtained without the need for overly sensitive or costly cameras. Further applicationsof this technique, such as its potential in testing new donor polymer formulations as well as its capacity to monitordegradation due to residual solvents, are briefly discussed.© (2012) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.