1
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Hammer S, Linderl T, Tvingstedt K, Brütting W, Pflaum J. Spectroscopic analysis of vibrational coupling in multi-molecular excited states. Mater Horiz 2023; 10:221-234. [PMID: 36367085 DOI: 10.1039/d2mh00829g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Multi-molecular excited states accompanied by intra- and inter-molecular geometric relaxation are commonly encountered in optical and electrooptical studies and applications of organic semiconductors as, for example, excimers or charge transfer states. Understanding the dynamics of these states is crucial to improve organic devices such as light emitting diodes and solar cells. Their full microscopic description, however, demands sophisticated tools such as ab initio quantum chemical calculations which come at the expense of high computational costs and are prone to errors by assumptions as well as iterative algorithmic procedures. Hence, the analysis of spectroscopic data is often conducted at a phenomenological level only. Here, we present a toolkit to analyze temperature dependent luminescence data and gain first insights into the relevant microscopic parameters of the molecular system at hand. By means of a Franck-Condon based approach considering a single effective inter-molecular vibrational mode and different potentials for the ground and excited state we are able to explain the luminescence spectra of such multi-molecular states. We demonstrate that by applying certain reasonable simplifications the luminescence of charge transfer states as well as excimers can be satisfactorily reproduced for temperatures ranging from cryogenics to above room temperature. We present a semi-classical and a quantum-mechanical description of our model and, for both cases, demonstrate its applicability by analyzing the temperature dependent luminescence of the amorphous donor-acceptor heterojunction tetraphenyldibenzoperiflanthene:C60 as well as polycrystalline zinc-phthalocyanine to reproduce the luminescence spectra and extract relevant system parameters such as the excimer binding energy.
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Affiliation(s)
- Sebastian Hammer
- Experimental Physics VI, Julius Maximilian University Würzburg, 97074 Würzburg, Germany.
| | - Theresa Linderl
- Institute of Physics, University of Augsburg, 86135 Augsburg, Germany
| | - Kristofer Tvingstedt
- Experimental Physics VI, Julius Maximilian University Würzburg, 97074 Würzburg, Germany.
| | - Wolfgang Brütting
- Institute of Physics, University of Augsburg, 86135 Augsburg, Germany
| | - Jens Pflaum
- Experimental Physics VI, Julius Maximilian University Würzburg, 97074 Würzburg, Germany.
- Bavarian Center for Applied Energy Research, 97074 Würzburg, Germany
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2
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Ortstein K, Hutsch S, Hambsch M, Tvingstedt K, Wegner B, Benduhn J, Kublitski J, Schwarze M, Schellhammer S, Talnack F, Vogt A, Bäuerle P, Koch N, Mannsfeld SCB, Kleemann H, Ortmann F, Leo K. Band gap engineering in blended organic semiconductor films based on dielectric interactions. Nat Mater 2021; 20:1407-1413. [PMID: 34112978 DOI: 10.1038/s41563-021-01025-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Accepted: 04/26/2021] [Indexed: 06/12/2023]
Abstract
Blending organic molecules to tune their energy levels is currently being investigated as an approach to engineer the bulk and interfacial optoelectronic properties of organic semiconductors. It has been proven that the ionization energy and electron affinity can be equally shifted in the same direction by electrostatic effects controlled by blending similar halogenated derivatives with different energetics. Here we show that the energy gap of organic semiconductors can also be tuned by blending. We use oligothiophenes with different numbers of thiophene rings as an example and investigate their structure and electronic properties. Photoelectron spectroscopy and inverse photoelectron spectroscopy show tunability of the single-particle gap, with the optical gaps showing similar, but smaller, effects. Theoretical analysis shows that this tuning is mainly caused by a change in the dielectric constant with blend ratio. Further studies will explore the practical impact of this energy-level engineering strategy for optoelectronic devices.
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Affiliation(s)
- Katrin Ortstein
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP) and Institute for Applied Physics, Technische Universität Dresden, Dresden, Germany
| | - Sebastian Hutsch
- Center for Advancing Electronics Dresden, Technische Universität Dresden, Dresden, Germany
- Technische Universität München, Department of Chemistry, Garching, Germany
| | - Mike Hambsch
- Center for Advancing Electronics Dresden, Technische Universität Dresden, Dresden, Germany
- Faculty of Electrical and Computer Engineering, Technische Universität Dresden, Dresden, Germany
| | - Kristofer Tvingstedt
- Lehrstuhl für Experimentelle Physik IV, Julius-Maximilians-Universität Würzburg, Würzburg, Germany
| | - Berthold Wegner
- Institut für Physik & IRIS Adlershof, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Johannes Benduhn
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP) and Institute for Applied Physics, Technische Universität Dresden, Dresden, Germany
| | - Jonas Kublitski
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP) and Institute for Applied Physics, Technische Universität Dresden, Dresden, Germany
| | - Martin Schwarze
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP) and Institute for Applied Physics, Technische Universität Dresden, Dresden, Germany
| | - Sebastian Schellhammer
- Center for Advancing Electronics Dresden, Technische Universität Dresden, Dresden, Germany
| | - Felix Talnack
- Center for Advancing Electronics Dresden, Technische Universität Dresden, Dresden, Germany
- Faculty of Electrical and Computer Engineering, Technische Universität Dresden, Dresden, Germany
| | - Astrid Vogt
- Institut für Organische Chemie II und Neue Materialien, Universität Ulm, Ulm, Germany
| | - Peter Bäuerle
- Institut für Organische Chemie II und Neue Materialien, Universität Ulm, Ulm, Germany
| | - Norbert Koch
- Institut für Physik & IRIS Adlershof, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Stefan C B Mannsfeld
- Center for Advancing Electronics Dresden, Technische Universität Dresden, Dresden, Germany
- Faculty of Electrical and Computer Engineering, Technische Universität Dresden, Dresden, Germany
| | - Hans Kleemann
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP) and Institute for Applied Physics, Technische Universität Dresden, Dresden, Germany
| | - Frank Ortmann
- Center for Advancing Electronics Dresden, Technische Universität Dresden, Dresden, Germany.
- Technische Universität München, Department of Chemistry, Garching, Germany.
| | - Karl Leo
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP) and Institute for Applied Physics, Technische Universität Dresden, Dresden, Germany.
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3
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Armer M, Höcker J, Büchner C, Häfele S, Dörflinger P, Sirtl MT, Tvingstedt K, Bein T, Dyakonov V. Influence of crystallisation on the structural and optical properties of lead-free Cs 2AgBiBr 6 perovskite crystals. CrystEngComm 2021. [DOI: 10.1039/d1ce00844g] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We compare the growth of Cs2AgBiBr6 crystals by slow and fast evaporation of organic solvents. Using different growth temperatures and precursors enables bridging the gap between the optical properties and applications of Cs2AgBiBr6 in solar cells.
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Affiliation(s)
- Melina Armer
- Experimental Physics 6 and Würzburg-Dresden Cluster of Excellence ct.qmat, Julius Maximilian University of Würzburg, 97074 Würzburg, Germany
| | - Julian Höcker
- Experimental Physics 6 and Würzburg-Dresden Cluster of Excellence ct.qmat, Julius Maximilian University of Würzburg, 97074 Würzburg, Germany
| | - Carsten Büchner
- Experimental Physics 6 and Würzburg-Dresden Cluster of Excellence ct.qmat, Julius Maximilian University of Würzburg, 97074 Würzburg, Germany
| | - Sophie Häfele
- Experimental Physics 6 and Würzburg-Dresden Cluster of Excellence ct.qmat, Julius Maximilian University of Würzburg, 97074 Würzburg, Germany
| | - Patrick Dörflinger
- Experimental Physics 6 and Würzburg-Dresden Cluster of Excellence ct.qmat, Julius Maximilian University of Würzburg, 97074 Würzburg, Germany
| | - Maximilian T. Sirtl
- Department of Chemistry and Centre for NanoScience (CeNS), University of Munich (LMU), 81377 Munich, Germany
| | - Kristofer Tvingstedt
- Experimental Physics 6 and Würzburg-Dresden Cluster of Excellence ct.qmat, Julius Maximilian University of Würzburg, 97074 Würzburg, Germany
| | - Thomas Bein
- Department of Chemistry and Centre for NanoScience (CeNS), University of Munich (LMU), 81377 Munich, Germany
| | - Vladimir Dyakonov
- Experimental Physics 6 and Würzburg-Dresden Cluster of Excellence ct.qmat, Julius Maximilian University of Würzburg, 97074 Würzburg, Germany
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4
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Höcker J, Kiermasch D, Rieder P, Tvingstedt K, Baumann A, Dyakonov V. Efficient Solution Processed CH3NH3PbI3 Perovskite Solar Cells with PolyTPD Hole Transport Layer. ACTA ACUST UNITED AC 2019. [DOI: 10.1515/zna-2019-0127] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
The organic and hydrophobic polymer poly[N, N′-bis(4-butilphenyl)-N, N′-bis(phenyl)-benzidine] (polyTPD) represents a promising hole transport layer (HTL) for perovskite photovoltaics due to its suitable energy levels, whereby its highest occupied molecular orbital level matches well with the valence band level of methylammonium lead triiodide (CH3NH3PbI3, MAPbI3) perovskite. However, processing a perovskite layer from the solution on the surface of this organic material, is found to be difficult due to the surface properties of the latter. In this study, we evaluate efficient p-i-n type MAPbI3 perovskite solar cells employing differently processed polyTPD layers. We found that the surface coverage of the MAPbI3 perovskite layer strongly depends on the preparation method of the underlying polyTPD layer. By varying the solvents for the polyTPD precursor, its concentration, and by applying an optimised two-step perovskite deposition technique we increased both the surface coverage of the perovskite layer as well as the power conversion efficiency (PCE) of the corresponding solar cell devices. Our simple solvent-engineering approach demonstrates that no further interface modifications are needed for a successful preparation of efficient planar photovoltaic devices with PCEs in the range of 15 %–16 %.
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Affiliation(s)
- Julian Höcker
- Experimental Physics VI , Julius Maximilian University of Würzburg , 97074 Würzburg , Germany
| | - David Kiermasch
- Experimental Physics VI , Julius Maximilian University of Würzburg , 97074 Würzburg , Germany
| | - Philipp Rieder
- Experimental Physics VI , Julius Maximilian University of Würzburg , 97074 Würzburg , Germany
| | - Kristofer Tvingstedt
- Experimental Physics VI , Julius Maximilian University of Würzburg , 97074 Würzburg , Germany
| | - Andreas Baumann
- Bavarian Center for Applied Energy Research (ZAE Bayern) , 97074 Würzburg , Germany
| | - Vladimir Dyakonov
- Experimental Physics VI , Julius Maximilian University of Würzburg , 97074 Würzburg , Germany
- Bavarian Center for Applied Energy Research (ZAE Bayern) , 97074 Würzburg , Germany
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5
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Ullbrich S, Benduhn J, Jia X, Nikolis VC, Tvingstedt K, Piersimoni F, Roland S, Liu Y, Wu J, Fischer A, Neher D, Reineke S, Spoltore D, Vandewal K. Emissive and charge-generating donor-acceptor interfaces for organic optoelectronics with low voltage losses. Nat Mater 2019; 18:459-464. [PMID: 30936478 DOI: 10.1038/s41563-019-0324-5] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Accepted: 02/19/2019] [Indexed: 06/09/2023]
Abstract
Intermolecular charge-transfer states at the interface between electron donating (D) and accepting (A) materials are crucial for the operation of organic solar cells but can also be exploited for organic light-emitting diodes1,2. Non-radiative charge-transfer state decay is dominant in state-of-the-art D-A-based organic solar cells and is responsible for large voltage losses and relatively low power-conversion efficiencies as well as electroluminescence external quantum yields in the 0.01-0.0001% range3,4. In contrast, the electroluminescence external quantum yield reaches up to 16% in D-A-based organic light-emitting diodes5-7. Here, we show that proper control of charge-transfer state properties allows simultaneous occurrence of a high photovoltaic and emission quantum yield within a single, visible-light-emitting D-A system. This leads to ultralow-emission turn-on voltages as well as significantly reduced voltage losses upon solar illumination. These results unify the description of the electro-optical properties of charge-transfer states in organic optoelectronic devices and foster the use of organic D-A blends in energy conversion applications involving visible and ultraviolet photons8-11.
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Affiliation(s)
- Sascha Ullbrich
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP) and Institute for Applied Physics, Technische Universität Dresden, Dresden, Germany.
| | - Johannes Benduhn
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP) and Institute for Applied Physics, Technische Universität Dresden, Dresden, Germany.
| | - Xiangkun Jia
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP) and Institute for Applied Physics, Technische Universität Dresden, Dresden, Germany
| | - Vasileios C Nikolis
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP) and Institute for Applied Physics, Technische Universität Dresden, Dresden, Germany
| | - Kristofer Tvingstedt
- Experimental Physics VI, Julius-Maximilian University of Würzburg, Würzburg, Germany
| | | | - Steffen Roland
- Institute of Physics and Astronomy, University of Potsdam, Potsdam, Germany
| | - Yuan Liu
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP) and Institute for Applied Physics, Technische Universität Dresden, Dresden, Germany
| | - Jinhan Wu
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP) and Institute for Applied Physics, Technische Universität Dresden, Dresden, Germany
| | - Axel Fischer
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP) and Institute for Applied Physics, Technische Universität Dresden, Dresden, Germany
| | - Dieter Neher
- Institute of Physics and Astronomy, University of Potsdam, Potsdam, Germany
| | - Sebastian Reineke
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP) and Institute for Applied Physics, Technische Universität Dresden, Dresden, Germany
| | - Donato Spoltore
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP) and Institute for Applied Physics, Technische Universität Dresden, Dresden, Germany
| | - Koen Vandewal
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP) and Institute for Applied Physics, Technische Universität Dresden, Dresden, Germany.
- Institute for Materials Research (IMO-IMOMEC), Hasselt University, Diepenbeek, Belgium.
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6
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Kudriashova LG, Kiermasch D, Rieder P, Campbell M, Tvingstedt K, Baumann A, Astakhov GV, Dyakonov V. Impact of Interfaces and Laser Repetition Rate on Photocarrier Dynamics in Lead Halide Perovskites. J Phys Chem Lett 2017; 8:4698-4703. [PMID: 28905628 DOI: 10.1021/acs.jpclett.7b02087] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
We studied charge carrier recombination in methylammonium lead iodide (MAPbI3) perovskite and the impact of interfaces on the charge carrier lifetime using time-resolved photoluminescence. Pristine films and those covered with organic electron and hole transport materials (ETM and HTM) were investigated at various laser repetition rates ranging from 10 kHz to 10 MHz in order to separate the bulk and interface-affected recombination. We revealed two different components in the PL decay. The fast component (shorter than 300 ns) is assigned to interfacial processes and the slow one to bulk recombination. A high repetition pulse train was shown to shorten PL decay in pristine perovskite while significantly prolonging the photocarrier lifetime in MAPbI3 covered by TMs. This effect can be qualitatively explained with a kinetic model taking interface traps into account. We demonstrate a significant influence of the excitation repetition rate on photocarrier lifetime, which should be considered when studying charge carrier dynamics in perovskites.
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Affiliation(s)
- Liudmila G Kudriashova
- Experimental Physics 6, Julius-Maximilian University of Würzburg , 97074 Würzburg, Germany
| | - David Kiermasch
- Experimental Physics 6, Julius-Maximilian University of Würzburg , 97074 Würzburg, Germany
| | - Philipp Rieder
- Experimental Physics 6, Julius-Maximilian University of Würzburg , 97074 Würzburg, Germany
| | - Marshall Campbell
- Experimental Physics 6, Julius-Maximilian University of Würzburg , 97074 Würzburg, Germany
| | - Kristofer Tvingstedt
- Experimental Physics 6, Julius-Maximilian University of Würzburg , 97074 Würzburg, Germany
| | - Andreas Baumann
- Bavarian Center for Applied Energy Research e.V. (ZAE Bayern) , 97074 Würzburg, Germany
| | - Georgy V Astakhov
- Experimental Physics 6, Julius-Maximilian University of Würzburg , 97074 Würzburg, Germany
| | - Vladimir Dyakonov
- Experimental Physics 6, Julius-Maximilian University of Würzburg , 97074 Würzburg, Germany
- Bavarian Center for Applied Energy Research e.V. (ZAE Bayern) , 97074 Würzburg, Germany
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7
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Abstract
Thermally stimulated current (TSC) measurements are used to characterize electronic trap states in methylammonium lead iodide perovsite solar cells. Several TSC peaks were observed over the temperature range from 20 K to room temperature. To elucidate the origins of these peaks, devices with various organic charge transport layers and devices without transport layers were tested. Two peaks appear at very low temperatures, indicating shallow trap states that are mainly attributed to the PCBM/C60 electron transport bilayer. However, two additional peaks appear at higher temperatures, that is, they are deeper in energy, and are assigned to the perovskite layer. At around T = 163 K, a sharp peak, also present in the dark TSC measurements, is assigned to the orthorhombic-tetragonal phase transition in the perovskite. However, a peak at around T = 191 K is assigned to trap states with activation energies of around 500 meV but with a rather low concentration of 1 × 10(21) m(-3).
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Affiliation(s)
- Andreas Baumann
- †Bavarian Center for Applied Energy Research e.V. (ZAE Bayern), 97074 Würzburg, Germany
| | - Stefan Väth
- ‡Experimental Physics VI, Julius-Maximilian University of Würzburg, 97074 Würzburg, Germany
| | - Philipp Rieder
- ‡Experimental Physics VI, Julius-Maximilian University of Würzburg, 97074 Würzburg, Germany
| | - Michael C Heiber
- §Institut für Physik, Technische Universität Chemnitz, 09126 Chemnitz, Germany
| | - Kristofer Tvingstedt
- ‡Experimental Physics VI, Julius-Maximilian University of Würzburg, 97074 Würzburg, Germany
- §Institut für Physik, Technische Universität Chemnitz, 09126 Chemnitz, Germany
| | - Vladimir Dyakonov
- †Bavarian Center for Applied Energy Research e.V. (ZAE Bayern), 97074 Würzburg, Germany
- ‡Experimental Physics VI, Julius-Maximilian University of Würzburg, 97074 Würzburg, Germany
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8
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Tvingstedt K, Malinkiewicz O, Baumann A, Deibel C, Snaith HJ, Dyakonov V, Bolink HJ. Radiative efficiency of lead iodide based perovskite solar cells. Sci Rep 2014; 4:6071. [PMID: 25317958 PMCID: PMC5377528 DOI: 10.1038/srep06071] [Citation(s) in RCA: 92] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2014] [Accepted: 07/28/2014] [Indexed: 12/23/2022] Open
Abstract
The maximum efficiency of any solar cell can be evaluated in terms of its corresponding ability to emit light. We herein determine the important figure of merit of radiative efficiency for Methylammonium Lead Iodide perovskite solar cells and, to put in context, relate it to an organic photovoltaic (OPV) model device. We evaluate the reciprocity relation between electroluminescence and photovoltaic quantum efficiency and conclude that the emission from the perovskite devices is dominated by a sharp band-to-band transition that has a radiative efficiency much higher than that of an average OPV device. As a consequence, the perovskite have the benefit of retaining an open circuit voltage ~0.14 V closer to its radiative limit than the OPV cell. Additionally, and in contrast to OPVs, we show that the photoluminescence of the perovskite solar cell is substantially quenched under short circuit conditions in accordance with how an ideal photovoltaic cell should operate.
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Affiliation(s)
- Kristofer Tvingstedt
- Experimental Physics VI, Julius-Maximillian University of Würzburg, 97074 Würzburg, Germany
| | - Olga Malinkiewicz
- Instituto de Ciencia Molecular, Universidad de Valencia, C/Catedrático J. Beltrán 2, 46980 Paterna, Valencia, Spain
| | - Andreas Baumann
- Bavarian Center for Applied Energy Research e.V. (ZAE Bayern), 97074 Würzburg, Germany
| | - Carsten Deibel
- Experimental Physics VI, Julius-Maximillian University of Würzburg, 97074 Würzburg, Germany
| | - Henry J Snaith
- University of Oxford, Clarendon Laboratory, Parks Road Oxford, OX1 3PU, United Kingdom
| | - Vladimir Dyakonov
- 1] Experimental Physics VI, Julius-Maximillian University of Würzburg, 97074 Würzburg, Germany [2] Bavarian Center for Applied Energy Research e.V. (ZAE Bayern), 97074 Würzburg, Germany
| | - Henk J Bolink
- Instituto de Ciencia Molecular, Universidad de Valencia, C/Catedrático J. Beltrán 2, 46980 Paterna, Valencia, Spain
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9
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Tang Z, Andersson LM, George Z, Vandewal K, Tvingstedt K, Heriksson P, Kroon R, Andersson MR, Inganäs O. Interlayer for modified cathode in highly efficient inverted ITO-free organic solar cells. Adv Mater 2012; 24:554-558. [PMID: 22250035 DOI: 10.1002/adma.201104579] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Inverted polymer solar cells with a bottom metal cathode modified by a conjugated polymer interlayer show considerable improvement of photocurrent and fill factor, which is due to hole blocking at the interlayer, and a modified surface energy which affects the nanostructure in the TQ1/[70]PCBM blend.
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Affiliation(s)
- Zheng Tang
- Biomolecular and Organic Electronics IFM, Center of Organic Electronics, Linköping University, SE-581 83 Linköping, Sweden.
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10
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Müller C, Bergqvist J, Vandewal K, Tvingstedt K, Anselmo AS, Magnusson R, Alonso MI, Moons E, Arwin H, Campoy-Quiles M, Inganäs O. Phase behaviour of liquid-crystalline polymer/fullerene organic photovoltaic blends: thermal stability and miscibility. ACTA ACUST UNITED AC 2011. [DOI: 10.1039/c1jm11239b] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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11
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Inganäs O, Zhang F, Tvingstedt K, Andersson LM, Hellström S, Andersson MR. Polymer photovoltaics with alternating copolymer/fullerene blends and novel device architectures. Adv Mater 2010; 22:E100-E116. [PMID: 20455208 DOI: 10.1002/adma.200904407] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
The synthesis of novel conjugated polymers, designed for the purpose of photovoltaic energy conversion, and their properties in polymer/fullerene materials and photovoltaic devices are reviewed. Two families of main-chain polymer donors, based on fluorene or phenylene and donor-acceptor-donor comonomers in alternating copolymers, are used to absorb the high-energy parts of the solar spectrum and to give high photovoltages in combinations with fullerene acceptors in devices. These materials are used in alternative photovoltaic device geometries with enhanced light incoupling to collect larger photocurrents or to enable tandem devices and enhance photovoltage.
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Affiliation(s)
- Olle Inganäs
- Center of Organic Electronics, Department of Physics, Linköping University, Sweden.
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12
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Gadisa A, Tvingstedt K, Vandewal K, Zhang F, Manca JV, Inganäs O. Bipolar charge transport in fullerene molecules in a bilayer and blend of polyfluorene copolymer and fullerene. Adv Mater 2010; 22:1008-1011. [PMID: 20217830 DOI: 10.1002/adma.200902579] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Affiliation(s)
- Abay Gadisa
- Institute for Materials Research, Hasselt University Wetenschapspark 1, 3590 Diepenbeek, Belgium.
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13
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Vandewal K, Tvingstedt K, Gadisa A, Inganäs O, Manca JV. On the origin of the open-circuit voltage of polymer-fullerene solar cells. Nat Mater 2009; 8:904-909. [PMID: 19820700 DOI: 10.1038/nmat2548] [Citation(s) in RCA: 283] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2009] [Accepted: 09/15/2009] [Indexed: 05/28/2023]
Abstract
The increasing amount of research on solution-processable, organic donor-acceptor bulk heterojunction photovoltaic systems, based on blends of conjugated polymers and fullerenes has resulted in devices with an overall power-conversion efficiency of 6%. For the best devices, absorbed photon-to-electron quantum efficiencies approaching 100% have been shown. Besides the produced current, the overall efficiency depends critically on the generated photovoltage. Therefore, understanding and optimization of the open-circuit voltage (Voc) of organic solar cells is of high importance. Here, we demonstrate that charge-transfer absorption and emission are shown to be related to each other and Voc in accordance with the assumptions of the detailed balance and quasi-equilibrium theory. We underline the importance of the weak ground-state interaction between the polymer and the fullerene and we confirm that Voc is determined by the formation of these states. Our work further suggests alternative pathways to improve Voc of donor-acceptor devices.
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Affiliation(s)
- Koen Vandewal
- IMEC-IMOMEC, vzw, Institute for Materials Research, Hasselt University, Wetenschapspark 1, 3590 Diepenbeek, Belgium.
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14
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Tvingstedt K, Vandewal K, Gadisa A, Zhang F, Manca J, Inganäs O. Electroluminescence from Charge Transfer States in Polymer Solar Cells. J Am Chem Soc 2009; 131:11819-24. [DOI: 10.1021/ja903100p] [Citation(s) in RCA: 314] [Impact Index Per Article: 20.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Kristofer Tvingstedt
- Biomolecular and Organic Electronics, Center of Organic Electronics (COE), Department of Physics, Chemistry and Biology, Linköping University, 58183 Linköping, Sweden, and IMEC-IMOMEC, vzw, Institute for Materials Research, Hasselt University, Wetenschapspark 1, 3590 Diepenbeek, Belgium
| | - Koen Vandewal
- Biomolecular and Organic Electronics, Center of Organic Electronics (COE), Department of Physics, Chemistry and Biology, Linköping University, 58183 Linköping, Sweden, and IMEC-IMOMEC, vzw, Institute for Materials Research, Hasselt University, Wetenschapspark 1, 3590 Diepenbeek, Belgium
| | - Abay Gadisa
- Biomolecular and Organic Electronics, Center of Organic Electronics (COE), Department of Physics, Chemistry and Biology, Linköping University, 58183 Linköping, Sweden, and IMEC-IMOMEC, vzw, Institute for Materials Research, Hasselt University, Wetenschapspark 1, 3590 Diepenbeek, Belgium
| | - Fengling Zhang
- Biomolecular and Organic Electronics, Center of Organic Electronics (COE), Department of Physics, Chemistry and Biology, Linköping University, 58183 Linköping, Sweden, and IMEC-IMOMEC, vzw, Institute for Materials Research, Hasselt University, Wetenschapspark 1, 3590 Diepenbeek, Belgium
| | - Jean Manca
- Biomolecular and Organic Electronics, Center of Organic Electronics (COE), Department of Physics, Chemistry and Biology, Linköping University, 58183 Linköping, Sweden, and IMEC-IMOMEC, vzw, Institute for Materials Research, Hasselt University, Wetenschapspark 1, 3590 Diepenbeek, Belgium
| | - Olle Inganäs
- Biomolecular and Organic Electronics, Center of Organic Electronics (COE), Department of Physics, Chemistry and Biology, Linköping University, 58183 Linköping, Sweden, and IMEC-IMOMEC, vzw, Institute for Materials Research, Hasselt University, Wetenschapspark 1, 3590 Diepenbeek, Belgium
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Hamedi M, Tvingstedt K, Karlsson RH, Asberg P, Inganas O. Bridging dimensions in organic electronics: assembly of electroactive polymer nanodevices from fluids. Nano Lett 2009; 9:631-635. [PMID: 19140695 DOI: 10.1021/nl802919w] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Processing and patterning of electroactive materials from solvents is a hallmark of flexible organic electronics, and commercial applications based on these properties are now emerging. Printing and ink-jetting are today preferred technologies for patterning, but these limit the formation of nanodevices, as they give structures way above the micrometer lateral dimension. There is therefore a great need for cheap, large area patterning of nanodevices and methods for top-down registration of these. Here we demonstrate large area patterning of connected micro/nanolines and nanotransistors from the conducting polymer PEDOT, assembled from fluids. We thereby simultaneously solve problems of large area nanopatterning, and nanoregistration.
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16
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Tvingstedt K, Dal Zilio S, Inganäs O, Tormen M. Trapping light with micro lenses in thin film organic photovoltaic cells. Opt Express 2008; 16:21608-21615. [PMID: 19104592 DOI: 10.1364/oe.16.021608] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
We demonstrate a novel light trapping configuration based on an array of micro lenses in conjunction with a self aligned array of micro apertures located in a highly reflecting mirror. When locating the light trapping element, that displays strong directional asymmetric transmission, in front of thin film organic photovoltaic cells, an increase in cell absorption is obtained. By recycling reflected photons that otherwise would be lost, thinner films with more beneficial electrical properties can effectively be deployed. The light trapping element enhances the absorption rate of the solar cell and increases the photocurrent by as much as 25%.
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Affiliation(s)
- Kristofer Tvingstedt
- Biomolecular and organic electronics, Center of Organic Electronics, IFM, Linköpings Universitet, SE-581 83 Linköping, Sweden.
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17
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Zhang F, Bijleveld J, Perzon E, Tvingstedt K, Barrau S, Inganäs O, Andersson MR. High photovoltage achieved in low band gap polymer solar cells by adjusting energy levels of a polymer with the LUMOs of fullerene derivatives. ACTA ACUST UNITED AC 2008. [DOI: 10.1039/b811957k] [Citation(s) in RCA: 132] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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