@article{53fbf772fb5041e19135fedada328895,
title = "Lyotropic Liquid Crystal Mediated Assembly of Donor Polymers Enhances Efficiency and Stability of Blade-Coated Organic Solar Cells",
abstract = "Conjugated polymers can undergo complex, concentration-dependent self-assembly during solution processing, yet little is known about its impact on film morphology and device performance of organic solar cells. Herein, lyotropic liquid crystal (LLC) mediated assembly across multiple conjugated polymers is reported, which generally gives rise to improved device performance of blade-coated non-fullerene bulk heterojunction solar cells. Using D18 as a model system, the formation mechanism of LLC is unveiled employing solution X-ray scattering and microscopic imaging tools: D18 first aggregates into semicrystalline nanofibers, then assemble into achiral nematic LLC which goes through symmetry breaking to yield a chiral twist-bent LLC. The assembly pathway is driven by increasing solution concentration – a common driving force during evaporative assembly relevant to scalable manufacturing. This assembly pathway can be largely modulated by coating regimes to give 1) lyotropic liquid crystalline assembly in the evaporation regime and 2) random fiber aggregation pathway in the Landau–Levich regime. The chiral liquid crystalline assembly pathway resulted in films with crystallinity 2.63 times that of films from the random fiber aggregation pathway, significantly enhancing the T80 lifetime by 50-fold. The generality of LLC-mediated assembly and enhanced device performance is further validated using polythiophene and quinoxaline-based donor polymers.",
keywords = "chiral symmetry breaking, liquid crystalline assembly, organic solar cells, polymer assembly, supramolecular chirality",
author = "Azzaya Khasbaatar and Damron, \{Alec M.\} and Fernando, \{Pravini S.\} and Williams, \{Jasmine S.\} and Chenhui Zhu and Gann, \{Eliot H.\} and Lee, \{Jong Hoon\} and Adrian Birge and Bora Kim and Sina Sabury and Lee, \{Minjoo L.\} and Reynolds, \{John R.\} and Ying Diao",
note = "A.K. and A.M.D. are co-first authors and contributed equally to this work. This work was primarily supported by the Office of Naval Research under grant number N00014-22-1-2202 (Y.D.). A.K. acknowledges the A. T. Widiger Chemical Engineering fellowship. P.F. and Y.D. acknowledge partial support by the NSF CAREER award under Grant No. 18\textbackslash{}u201347828 and by the Air Force Office of Scientific Research (AFOSR) under the Multidisciplinary University Research Initiative (MURI) with grant number FA9550-23-1-0311. Y.D. and A.M.D. acknowledge partial support by the NSF Center for Complex Particle Systems (COMPASS) under grant number 2243104.\textbackslash{}u00A0This research used resources from the Advanced Light Source, a U.S. DOE Office of Science User Facility under contract no. DE-AC02-05CH11231 and the LiX beamline at National Synchrotron Light Source II, which is part of the Center for BioMolecular Structure (CBMS) primarily supported by the National Institutes of Health, National Institute of General Medical Sciences (NIGMS) through a P30 Grant (P30GM133893), and by the DOE Office of Biological and Environmental Research (KP1605010). LiX also received additional support from NIH Grant S10 OD012331. As part of NSLS-II, a national user facility at Brookhaven National Laboratory, work performed at the CBMS is supported in part by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences Program under contract number DE-SC0012704. The research also used facilities of the Materials Research Laboratory Central Research Facilities, University of Illinois. The authors thank Dr. Lin Yang from National Synchrotron Light Source II for support on SAXS measurements, Dr. Kathy Walsh from Materials Research Laboratory at the University of Illinois for support on PiFM measurements A.K. and A.M.D. are co\textbackslash{}u2010first authors and contributed equally to this work. This work was primarily supported by the Office of Naval Research under grant number N00014\textbackslash{}u201022\textbackslash{}u20101\textbackslash{}u20102202 (Y.D.). A.K. acknowledges the A. T. Widiger Chemical Engineering fellowship. P.F. and Y.D. acknowledge partial support by the NSF CAREER award under Grant No. 18\textbackslash{}u201347828 and by the Air Force Office of Scientific Research (AFOSR) under the Multidisciplinary University Research Initiative (MURI) with grant number FA9550\textbackslash{}u201023\textbackslash{}u20101\textbackslash{}u20100311. Y.D. and A.M.D. acknowledge partial support by the NSF Center for Complex Particle Systems (COMPASS) under grant number 2243104. This research used resources from the Advanced Light Source, a U.S. DOE Office of Science User Facility under contract no. DE\textbackslash{}u2010AC02\textbackslash{}u201005CH11231 and the LiX beamline at National Synchrotron Light Source II, which is part of the Center for BioMolecular Structure (CBMS) primarily supported by the National Institutes of Health, National Institute of General Medical Sciences (NIGMS) through a P30 Grant (P30GM133893), and by the DOE Office of Biological and Environmental Research (KP1605010). LiX also received additional support from NIH Grant S10 OD012331. As part of NSLS\textbackslash{}u2010II, a national user facility at Brookhaven National Laboratory, work performed at the CBMS is supported in part by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences Program under contract number DE\textbackslash{}u2010SC0012704. The research also used facilities of the Materials Research Laboratory Central Research Facilities, University of Illinois. The authors thank Dr. Lin Yang from National Synchrotron Light Source II for support on SAXS measurements, Dr. Kathy Walsh from Materials Research Laboratory at the University of Illinois for support on PiFM measurements",
year = "2025",
month = mar,
day = "19",
doi = "10.1002/adma.202414632",
language = "English (US)",
volume = "37",
journal = "Advanced Materials",
issn = "0935-9648",
publisher = "Wiley-Blackwell",
number = "11",
}