Son, Seon Kyoung Lee, Hyo-Sang Ha, Jae Seung Kim, Kyung Hwan Son, Hae Jung Ko, Min Jae Kim, Honggon Lee, Doh-Kwon Kim, Jin Young Lee, Wonmok Park, Sungnam Choi, Dong Hoon Kim, BongSoo 2024-01-20T10:00:53Z 2024-01-20T10:00:53Z 2021-09-05 2014-05 0927-0248 https://pubs.kist.re.kr/handle/201004/126834 In this study, we demonstrated the effective morphological control of polymer:fullerene blends using three separate solvent systems: chloroform (CF), CF:1,8-diiodooctane (DIO), and CF:o-dichlorobenzene (ODCB). The polymer:fullerene blends are composed of two diketopyrrolopyrrole (DPP)-based polymers of P(DPP-alt-QT) and P(DPP-alt-DTBSe) and a fullerene derivative of [6,6]-phenyl-C71-butyric acid methyl ester (PC71BM), i.e., P(DPP-alt-QT):PC71BM or P(DPP-alt-DTBSe):PCTIBM. The CF:ODCB binary solvent exhibited the best photovoltaic performance among the three solvent systems for both polymer-based devices, although the CF:DIO also exhibited an improved performance compared to the CF system. By examining film morphology of the blend films, we found that the CF:ODCB enabled the most optimal nanoscale phase separation and the morphological features were strongly affected by the solubility of each material in the high boiling-point (BP) solvent. Specifically, the polymers have limited but slightly higher solubility in ODCB than in DIO, while the PC71BM molecules have a high solubility in both DIO and ODCB. Therefore, this work highlights that the optimally asymmetric solubility of each photoactive component in the high BP solvent is a critical factor to form the nanoscale, bicontinuous domains in the blend films and thereby to determine the performance of photovoltaic devices. (C) 2014 Elsevier B.V. All rights reserved. English ELSEVIER CONJUGATED POLYMER NANOSCALE MORPHOLOGY PHOTOVOLTAIC CELLS EFFICIENCY DONOR BAND SELENOPHENE MOBILITY VOLTAGE OXIDE Effect of asymmetric solubility of diketopyrrolopyrrole-based polymers and PC71BMs in a binary solvent system on the performance of bulk heterojunction solar cells Article 10.1016/j.solmat.2014.02.011 1 SOLAR ENERGY MATERIALS AND SOLAR CELLS, v.124, pp.232 - 240 SOLAR ENERGY MATERIALS AND SOLAR CELLS 124 232 240 scie scopus 000335111000030 2-s2.0-84897821422 Energy & Fuels Materials Science, Multidisciplinary Physics, Applied Energy & Fuels Materials Science Physics Article CONJUGATED POLYMER NANOSCALE MORPHOLOGY PHOTOVOLTAIC CELLS EFFICIENCY DONOR BAND SELENOPHENE MOBILITY VOLTAGE OXIDE Organic photovoltaics Power conversion efficiency Binary solvent system Morphology Hole mobility Polymer solar cell