TY  - JOUR
A1  - Grell, M.
A1  - Knoll, W.
A1  - Lupo, D.
A1  - Meisel, A.
A1  - Miteva, T.
A1  - Neher, Dieter
A1  - Nothofer, Heinz-Georg
A1  - Scherf, Ullrich
A1  - Yasuda, H.
T1  - Blue polarized electroluminescence from a liquid crystalline polyfluorene
Y1  - 1999
ER  - 
TY  - JOUR
A1  - Yang, X. H.
A1  - Jaiser, Frank
A1  - Klinger, S
A1  - Neher, Dieter
T1  - Blue polymer electrophosphorescent devices with different electron-transporting oxadiazoles
N2  - We report that the performances of blue polymer electrophosphorescent devices are crucially depending on the choice of the electron transporting material incorporated into the emissive layer. Devices with 1,3-bis[(4-tert- butylphenyl)-1,3,4-oxidiazolyl]phenylene (OXD-7) doped at similar to 40 wt% into a poly(vinylcarbazole) matrix exhibited significantly higher efficiencies than those with 2-(4-biphenylyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (PBD), yielding maximum luminous and power efficiency values of 18.2 Cd/A and 8.8 lm/W, respectively. Time resolved photoluminescence measurements revealed a long lifetime phosphorescence component in layers with PBD, which we assign to significant triplet harvesting by this electron-transporting component. (c) 2006 American Institute of Physics
Y1  - 2006
UR  - http://scitation.aip.org/getpdf/servlet/ GetPDFServlet?filetype=pdf&id=APPLAB000088000002021107000001&idtype=cvips&doi=10.1063/1.2162693&prog=normal
U6  - https://doi.org/10.1063/1.2162693
ER  - 
TY  - JOUR
A1  - Li, Tian-yi
A1  - Benduhn, Johannes
A1  - Li, Yue
A1  - Jaiser, Frank
A1  - Spoltore, Donato
A1  - Zeika, Olaf
A1  - Ma, Zaifei
A1  - Neher, Dieter
A1  - Vandewal, Koen
A1  - Leo, Karl
T1  - Boron dipyrromethene (BODIPY) with meso-perfluorinated alkyl substituents as near infrared donors in organic solar cells
JF  - Journal of materials chemistry : A, Materials for energy and sustainability
N2  - Three furan-fused BODIPYs were synthesized with perfluorinated methyl, ethyl and n-propyl groups on the meso-carbon. They were obtained with high yields by reacting the furan-fused 2-carboxylpyrrole in corresponding perfluorinated acid and anhydride. With the increase in perfluorinated alkyl chain length, the molecular packing in the single crystal is influenced, showing increasing stacking distance and decreasing slope angle. All the BODIPYs were characterized as intense absorbers in near infrared region in solid state, peaking at similar to 800 nm with absorption coefficient of over 280 000 cm(-1). Facilitated by high thermal stability, the furan-fused BODIPYs were employed in vacuum-deposited organic solar cells as electron donors. All devices exhibit PCE over 6.0% with the EQE maximum reaching 70% at similar to 790 nm. The chemical modification of the BODIPY donors have certain influence on the active layer morphology, and the highest PCE of 6.4% was obtained with a notably high jsc of 13.6 mA cm(-2). Sensitive EQE and electroluminance studies indicated that the energy losses generated by the formation of a charge transfer state and the radiative recombination at the donor-acceptor interface were comparable in the range of 0.14-0.19 V, while non-radiative recombination energy loss of 0.38 V was the main energy loss route resulting in the moderate V-oc of 0.76 V.
Y1  - 2018
U6  - https://doi.org/10.1039/c8ta06261g
SN  - 2050-7488
SN  - 2050-7496
VL  - 6
IS  - 38
SP  - 18583
EP  - 18591
PB  - Royal Society of Chemistry
CY  - Cambridge
ER  - 
TY  - JOUR
A1  - Steyrleuthner, Robert
A1  - Schubert, Marcel
A1  - Jaiser, Frank
A1  - Blakesley, James C.
A1  - Chen, Zhihua
A1  - Facchetti, Antonio
A1  - Neher, Dieter
T1  - Bulk electron transport and charge injection in a high mobility n-type semiconducting polymer
N2  - Bulk electron transport in a high mobility n-type polymer is studied by time-of-flight photocurrent measurements and electron-only devices. Bulk electron mobilities of similar to 5 x 10(-3) cm(2)/Vs are obtained. The analysis of the electron currents suggests the presence of an injection barrier for all conventionally used low workfunction cathodes.
Y1  - 2010
UR  - http://www3.interscience.wiley.com/cgi-bin/jhome/10008336
U6  - https://doi.org/10.1002/adma.201000232
SN  - 0935-9648
ER  - 
TY  - JOUR
A1  - Bauer, C.
A1  - Böhmer, Roland
A1  - Moreno-Flores, S.
A1  - Richert, R.
A1  - Sillescu, H.
A1  - Neher, Dieter
T1  - Capacitive scanning dilatometry and frequency dependent thermal expansion of polymer films
Y1  - 2000
ER  - 
TY  - GEN
A1  - Liu, W.
A1  - Tkachov, R.
A1  - Komber, H.
A1  - Senkovskyy, V.
A1  - Schubert, M.
A1  - Wei, Z.
A1  - Facchetti, A.
A1  - Neher, Dieter
A1  - Kiriy, A.
T1  - Chain-growth polycondensation of perylene diimide-based copolymers
BT  - a new route to regio-regular perylene diimide-based acceptors for all-polymer solar cells and n-type transistors
N2  - Herein, we report the chain-growth tin-free room temperature polymerization method to synthesize n-type perylene diimide-dithiophene-based conjugated polymers (PPDIT2s) suitable for solar cell and transistor applications. The palladium/electron-rich tri-tert-butylphosphine catalyst is effective to enable the chain-growth polymerization of anion-radical monomer Br-TPDIT-Br/Zn to PPDIT2 with a molecular weight up to Mw ≈ 50 kg mol−1 and moderate polydispersity. This is the second example of the polymerization of unusual anion-radical aromatic complexes formed in a reaction of active Zn and electron-deficient diimide-based aryl halides. As such, the discovered polymerization method is not a specific reactivity feature of the naphthalene-diimide derivatives but is rather a general polymerization tool. This is an important finding, given the significantly higher maximum external quantum efficiency that can be reached with PDI-based copolymers (32–45%) in all-polymer solar cells compared to NDI-based materials (15–30%). Our studies revealed that PPDIT2 synthesized by the new method and the previously published polymer prepared by step-growth Stille polycondensation show similar electron mobility and all-polymer solar cell performance. At the same time, the polymerization reported herein has several technological advantages as it proceeds relatively fast at room temperature and does not involve toxic tin-based compounds. Because several chain-growth polymerization reactions are well-suited for the preparation of well-defined multi-functional polymer architectures, the next target is to explore the utility of the discovered polymerization in the synthesis of end-functionalized polymers and block copolymers. Such materials would be helpful to improve the nanoscale morphology of polymer blends in all-polymer solar cells.
T3  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 273 
Y1  - 2014
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-98724
ER  - 
TY  - JOUR
A1  - Liu, W.
A1  - Tkachov, R.
A1  - Komber, H.
A1  - Senkovskyy, V.
A1  - Schubert, M.
A1  - Wei, Z.
A1  - Facchetti, A.
A1  - Neher, Dieter
A1  - Kiriy, A.
T1  - Chain-growth polycondensation of perylene diimide-based copolymers: a new route to regio-regular perylene diimide-based acceptors for all-polymer solar cells and n-type transistors
JF  - Polymer Chemistry
N2  - Herein, we report the chain-growth tin-free room temperature polymerization method to synthesize n-type perylene diimide-dithiophene-based conjugated polymers (PPDIT2s) suitable for solar cell and transistor applications. The palladium/electron-rich tri-tert-butylphosphine catalyst is effective to enable the chain-growth polymerization of anion-radical monomer Br-TPDIT-Br/Zn to PPDIT2 with a molecular weight up to M-w approximate to 50 kg mol(-1) and moderate polydispersity. This is the second example of the polymerization of unusual anion-radical aromatic complexes formed in a reaction of active Zn and electron-deficient diimide-based aryl halides. As such, the discovered polymerization method is not a specific reactivity feature of the naphthalene-diimide derivatives but is rather a general polymerization tool. This is an important finding, given the significantly higher maximum external quantum efficiency that can be reached with PDI-based copolymers (32-45%) in all-polymer solar cells compared to NDI-based materials (15-30%). Our studies revealed that PPDIT2 synthesized by the new method and the previously published polymer prepared by step-growth Stille polycondensation show similar electron mobility and all-polymer solar cell performance. At the same time, the polymerization reported herein has several technological advantages as it proceeds relatively fast at room temperature and does not involve toxic tin-based compounds. Because several chain-growth polymerization reactions are well-suited for the preparation of well-defined multi-functional polymer architectures, the next target is to explore the utility of the discovered polymerization in the synthesis of end-functionalized polymers and block copolymers. Such materials would be helpful to improve the nanoscale morphology of polymer blends in all-polymer solar cells.
Y1  - 2014
U6  - https://doi.org/10.1039/c3py01707a
SN  - 1759-9954
SN  - 1759-9962
VL  - 5
IS  - 10
SP  - 3404
EP  - 3411
PB  - Royal Society of Chemistry
CY  - Cambridge
ER  - 
TY  - JOUR
A1  - Laquai, Frederic
A1  - Andrienko, Denis
A1  - Deibel, Carsten
A1  - Neher, Dieter
T1  - Charge carrier generation, recombination, and extraction in polymer-fullerene bulk heterojunction organic solar cells
JF  - Elementary processes in organic photovoltaics
N2  - In this chapter we review the basic principles of photocurrent generation in bulk heterojunction organic solar cells, discuss the loss channels limiting their efficiency, and present case studies of several polymer-fullerene blends. Using steady-state and transient, optical, and electrooptical techniques, we create a precise picture of the fundamental processes that ultimately govern solar cell efficiency.
KW  - Charge extraction
KW  - Charge generation
KW  - Charge recombination
KW  - Organic solar cells
KW  - PBT7
KW  - PBTTT
KW  - PCPDTBT
Y1  - 2026
SN  - 978-3-319-28338-8
SN  - 978-3-319-28336-4
U6  - https://doi.org/10.1007/978-3-319-28338-8_11
SN  - 0065-3195
VL  - 272
SP  - 267
EP  - 291
PB  - Springer
CY  - Berlin
ER  - 
TY  - JOUR
A1  - Däubler, Thomas Karl
A1  - Bittner, Reinhard
A1  - Meerholz, Klaus
A1  - Neher, Dieter
T1  - Charge carrier photogeneration, trapping and space-charge field formation in PVK-based photorefractive materials
Y1  - 2000
ER  - 
TY  - JOUR
A1  - Paulke, Andreas
A1  - Stranks, Samuel D.
A1  - Kniepert, Juliane
A1  - Kurpiers, Jona
A1  - Wolff, Christian Michael
A1  - Schön, Natalie
A1  - Snaith, Henry J.
A1  - Brenner, Thomas J. K.
A1  - Neher, Dieter
T1  - Charge carrier recombination dynamics in perovskite and polymer solar cells
JF  - Applied physics letters
N2  - Time-delayed collection field experiments are applied to planar organometal halide perovskite (CH3NH3PbI3) based solar cells to investigate charge carrier recombination in a fully working solar cell at the nanosecond to microsecond time scale. Recombination of mobile (extractable) charges is shown to follow second-order recombination dynamics for all fluences and time scales tested. Most importantly, the bimolecular recombination coefficient is found to be time-dependent, with an initial value of ca. 10(-9) cm(3)/s and a progressive reduction within the first tens of nanoseconds. Comparison to the prototypical organic bulk heterojunction device PTB7:PC71BM yields important differences with regard to the mechanism and time scale of free carrier recombination. (C) 2016 AIP Publishing LLC.
Y1  - 2016
U6  - https://doi.org/10.1063/1.4944044
SN  - 0003-6951
SN  - 1077-3118
VL  - 108
SP  - 252
EP  - 262
PB  - American Institute of Physics
CY  - Melville
ER  -