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  • 1.
    Barbero, David
    et al.
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Boulanger, Nicolas
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Ramstedt, Madeleine
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Yu, Junchun
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Carbon nanotube networks: nano-engineering of SWNT networks for enhanced charge transport at ultralow nanotube loading2014In: Advanced Materials, ISSN 0935-9648, E-ISSN 1521-4095, Vol. 26, no 19, p. 3164-Article in journal (Refereed)
    Abstract [en]

    Arrays of nano-engineered carbon nanotube networks embedded in nanoscale polymer structures enable highly efficient charge transport as demonstrated by D. R. Barbero and co-workers on page 3111. An increase in charge transport by several orders of magnitude is recorded at low nanotube loading compared to traditional random networks in either insulating (polystyrene) or semiconducting (polythiophene) polymers. These novel networks are expected to enhance the performance of next generation hybrid and carbon based photovoltaic devices.

  • 2.
    Barbero, David
    et al.
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Boulanger, Nicolas
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Ramstedt, Madeleine
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Yu, Junchun
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Nano-engineering of SWNT networks for enhanced charge transport at ultralow nanotube loading2014In: Advanced Materials, ISSN 0935-9648, E-ISSN 1521-4095, Vol. 26, no 19, p. 3111-3117Article in journal (Refereed)
    Abstract [en]

    We demonstrate a simple and controllable method to form periodic arrays of highly conductive nano-engineered single wall carbon nanotube networks from solution. These networks increase the conductivity of a polymer composite by as much as eight orders of magnitude compared to a traditional random network. These nano-engineered networks are demonstrated in both polystyrene and polythiophene polymers.

  • 3.
    Barbero, David R.
    et al.
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Stranks, Samuel D.
    Functional single-walled carbon nanotubes and nanoengineered networks for organic- and Perovskite-solar-cell applications2016In: Advanced Materials, ISSN 0935-9648, E-ISSN 1521-4095, Vol. 28, no 44, p. 9668-9685Article in journal (Refereed)
    Abstract [en]

    Carbon nanotubes have a variety of remarkable electronic and mechanical properties that, in principle, lend them to promising optoelectronic applications. However, the field has been plagued by heterogeneity in the distributions of synthesized tubes and uncontrolled bundling, both of which have prevented nanotubes from reaching their full potential. Here, a variety of recently demonstrated solution-processing avenues is presented, which may combat these challenges through manipulation of nanoscale structures. Recent advances in polymer-wrapping of single-walled carbon nanotubes (SWNTs) are shown, along with how the resulting nanostructures can selectively disperse tubes while also exploiting the favorable properties of the polymer, such as light-harvesting ability. New methods to controllably form nanoengineered SWNT networks with controlled nanotube placement are discussed. These nanoengineered networks decrease bundling, lower the percolation threshold, and enable a strong enhancement in charge conductivity compared to random networks, making them potentially attractive for optoelectronic applications. Finally, SWNT applications, to date, in organic and perovskite photovoltaics are reviewed, and insights as to how the aforementioned recent advancements can lead to improved device performance provided.

  • 4.
    Du, Hao
    et al.
    Institute of Materials Research, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, 518055 China.
    Wang, Yadong
    Institute of Materials Research, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, 518055 China.
    Kang, Yuqiong
    Institute of Materials Research, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, 518055 China.
    Zhao, Yun
    Institute of Materials Research, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, 518055 China.
    Tian, Yao
    Institute of Materials Research, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, 518055 China.
    Wang, Xianshu
    National and Local Joint Engineering Research Center of Lithium-ion Batteries and Materials Preparation Technology, Key Laboratory of Advanced Battery Materials of Yunnan Province, Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming, 650093 P. R. China.
    Tan, Yihong
    School of Chemistry and Chemical Engineering, Frontiers Science Center for Transformative Molecules, Shanghai Jiao Tong University, Shanghai, 200240 China.
    Liang, Zheng
    School of Chemistry and Chemical Engineering, Frontiers Science Center for Transformative Molecules, Shanghai Jiao Tong University, Shanghai, 200240 China.
    Wozny, John
    Department of Chemistry and Biochemistry, Northern Illinois University, DeKalb, IL, 60115 USA.
    Li, Tao
    Department of Chemistry and Biochemistry, Northern Illinois University, DeKalb, IL, 60115 USA.
    Ren, Dongsheng
    Institute of Nuclear & New Energy Technology, Tsinghua University, Beijing, 100084 China.
    Wang, Li
    Institute of Nuclear & New Energy Technology, Tsinghua University, Beijing, 100084 China.
    He, Xiangming
    Institute of Nuclear & New Energy Technology, Tsinghua University, Beijing, 100084 China.
    Xiao, Peitao
    College of Aerospace Science and Engineering, National University of Defense Technology, Changsha, 410073 China.
    Mao, Eryang
    State Key Laboratory of Catalysis, Dalian National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023 China.
    Tavajohi, Naser
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Kang, Feiyu
    Institute of Materials Research, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, 518055 China.
    Li, Baohua
    Institute of Materials Research, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, 518055 China.
    Side reactions/changes in lithium-ion batteries: mechanisms and strategies for creating safer and better batteries2024In: Advanced Materials, ISSN 0935-9648, E-ISSN 1521-4095Article, review/survey (Refereed)
    Abstract [en]

    Abstract Lithium-ion batteries (LIBs), in which lithium ions function as charge carriers, are considered the most competitive energy storage devices due to their high energy and power density. However, battery materials, especially with high capacity undergo side reactions and changes that result in capacity decay and safety issues. A deep understanding of the reactions that cause changes in the battery's internal components and the mechanisms of those reactions is needed to build safer and better batteries. This review focuses on the processes of battery failures, with voltage and temperature as the underlying factors. Voltage-induced failures result from anode interfacial reactions, current collector corrosion, cathode interfacial reactions, overcharge, and overdischarge, while temperature-induced failure mechanisms include SEI decomposition, separator damage, and interfacial reactions between electrodes and electrolytes. The review also presents protective strategies for controlling these reactions. As a result, the reader is offered a comprehensive overview of the safety features and failure mechanisms of various LIB components. 

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  • 5. Du, Mingrun
    et al.
    Yao, Mingguang
    Dong, JiaJun
    Ge, Peng
    Dong, Qing
    Kováts, Éva
    Pekker, Sándor
    Chen, Shuanglong
    Liu, Ran
    Liu, Bo
    Cui, Tian
    Sundqvist, Bertil
    Umeå University, Faculty of Science and Technology, Department of Physics. State Key Laboratory of Superhard Materials College of Physics Jilin University, Changchun, China.
    Liu, Bingbing
    New ordered structure of amorphous carbon clusters induced by fullerene-cubane reactions2018In: Advanced Materials, ISSN 0935-9648, E-ISSN 1521-4095, Vol. 30, article id 1706916Article in journal (Refereed)
    Abstract [en]

    As a new category of solids, crystalline materials constructed with amorphous building blocks expand the structure categorization of solids, for which designing such new structures and understanding the corresponding formation mechanisms are fundamentally important. Unlike previous reports, new amorphous carbon clusters constructed ordered carbon phases are found here by compressing C8H8/C60 cocrystals, in which the highly energetic cubane (C8H8) exhibits unusual roles as to the structure formation and transformations under pressure. The significant role of C8H8 is to stabilize the boundary interactions of the highly compressed or collapsed C60 clusters which preserves their long‐range ordered arrangement up to 45 GPa. With increasing time at high pressure, the gradual random bonding between C8H8 and carbon clusters, due to “energy release” of highly compressed cubane, leads to the loss of the ability of C8H8 to stabilize the carbon cluster arrangement. Thus a transition from short‐range disorder to long‐range disorder (amorphization) occurs in the formed material. The spontaneous bonding reconstruction most likely results in a 3D network in the material, which can create ring cracks on diamond anvils.

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  • 6. Ortony, Julia
    et al.
    Yang, Reiquyang
    Brzezinski, Jacek
    Edman, Ludvig
    Umeå University, Faculty of Science and Technology, Physics.
    Nguyen, Thuq
    Bazan, Guillermo
    Thermal Properties of Conjugated Polyelectrolytes.2008In: Advanced Materials, ISSN 0935-9648, E-ISSN 1521-4095, Vol. 20, no 2, p. 298-302Article in journal (Refereed)
  • 7.
    Ràfols-Ribé, Joan
    et al.
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Zhang, Xiaoying
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Larsen, Christian
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Lundberg, Petter
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Lindh, E. Mattias
    RISE Energy Technology Center AB, Piteå, Sweden.
    Mai, Cuc Thu
    Department of Chemistry − Ångström Laboratory, Uppsala University, Uppsala, Sweden.
    Mindemark, Jonas
    Department of Chemistry − Ångström Laboratory, Uppsala University, Uppsala, Sweden.
    Gracia-Espino, Eduardo
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Edman, Ludvig
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Controlling the emission zone by additives for improved light‐emitting electrochemical cells2022In: Advanced Materials, ISSN 0935-9648, E-ISSN 1521-4095, Vol. 34, no 8, article id 2107849Article in journal (Refereed)
    Abstract [en]

    The position of the emission zone (EZ) in the active material of a light-emitting electrochemical cell (LEC) has a profound influence on its performance because of microcavity effects and doping- and electrode-induced quenching. Previous attempts of EZ control have focused on the two principal constituents in the active material—the organic semiconductor (OSC) and the mobile ions—but this study demonstrates that it is possible to effectively control the EZ position through the inclusion of an appropriate additive into the active material. More specifically, it is shown that a mere modification of the end group on an added neutral compound, which also functions as an ion transporter, results in a shifted EZ from close to the anode to the center of the active material, which translates into a 60% improvement of the power efficiency. This particular finding is rationalized by a lowering of the effective electron mobility of the OSC through specific additive: OSC interactions, but the more important generic conclusion is that it is possible to control the EZ position, and thereby the LEC performance, by the straightforward inclusion of an easily tuned additive in the active material.

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  • 8.
    Sandström, Andreas
    et al.
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Asadpoordarvish, Amir
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Enevold, Jenny
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Edman, Ludvig
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Spraying Light: Ambient-Air Fabrication of Large-Area Emissive Devices on Complex-Shaped Surfaces2014In: Advanced Materials, ISSN 0935-9648, E-ISSN 1521-4095, Vol. 26, no 29, p. 4975-4980Article in journal (Refereed)
    Abstract [en]

    Light-emitting electrochemical cells, featuring uniform and efficient light emission over areas of 200 cm(2), are fabricated under ambient air with a for-the-purpose developed "spray-sintering" process. This fault-tolerant fabrication technique can also produce multicolored emission patterns via sequential deposition of different inks based on identical solvents. Significantly, additive spray-sintering using a mobile airbrush allows a straightforward addition of emissive function onto a wide variety of complex-shaped surfaces, as exemplified by the realization of a light-emitting kitchenware fork.

  • 9.
    Skrypnychuk, Vasyl
    et al.
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Wetzelaer, Gert-Jan A. H.
    Gordiichuk, Pavlo I.
    Mannsfeld, Stefan C. B.
    Herrmann, Andreas
    Toney, Michael F.
    Barbero, David R.
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Ultrahigh Mobility in an Organic Semiconductor by Vertical Chain Alignment2016In: Advanced Materials, ISSN 0935-9648, E-ISSN 1521-4095, Vol. 28, no 12, p. 2359-2366Article in journal (Refereed)
    Abstract [en]

    A method to produce highly efficient and long-range vertical charge transport is demonstrated in an undoped polythiophene thin film, with average mobilities above 3.1 cm(2) V-1 s(-1). These record high mobilities are achieved by controlled orientation of the polymer crystallites enabling the most efficient and fastest charge transport along the chain backbones and across multiple chains. The significant increase in mobility shown here may present a new route to producing faster and more efficient optoelectronic devices based on organic materials. [GRAPHICS] .

  • 10. Wang, Lin
    et al.
    Liu, Bingbing
    Liu, Dedi
    Yao, Mingguang
    Hou, Yuanyuan
    Yu, Shidan
    Cui, Tian
    Zou, Guangtian
    Iwasiewicz, Agnieszka
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Sundqvist, Bertil
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Synthesis of thin, rectangular C60 nanorods using m-xylene as shape controller2006In: Advanced Materials, ISSN 0935-9648, E-ISSN 1521-4095, Vol. 18, no 14, p. 1883-1888Article in journal (Refereed)
    Abstract [en]

    Thin, rectangular C60 nanorods in face-centered cubic structure are synthesized by using m-xylene as a shape controller. These unusual nanorods can easily grow on various substrates. The smallest nanorods have widths smaller than 30 nm. The nanorods are highly crystalline in single phase. A significant expansion of the lattice constant is also found in the C60 nanorods when their widths decrease below about 80 nm.

     

  • 11. Wu, Jingjie
    et al.
    Sharifi, Tiva
    Umeå University, Faculty of Science and Technology, Department of Physics. Department of Materials Science and NanoEngineering, Rice University, Houston, TX 77005, USA.
    Gao, Ying
    Zhang, Tianyu
    Ajayan, Pulickel M.
    Emerging Carbon-Based Heterogeneous Catalysts for Electrochemical Reduction of Carbon Dioxide into Value-Added Chemicals2019In: Advanced Materials, ISSN 0935-9648, E-ISSN 1521-4095, Vol. 31, no 13, article id 1804257Article, review/survey (Refereed)
    Abstract [en]

    The electrocatalytic reduction of CO2 provides a sustainable way to mitigate CO2 emissions, as well as store intermittent electrical energy into chemicals. However, its slow kinetics and the lack of ability to control the products of the reaction inhibit its industrial applications. In addition, the immature mechanistic understanding of the reduction process makes it difficult to develop a selective, scalable, and stable electrocatalyst. Carbon-based materials are widely considered as a stable and abundant alternative to metals for catalyzing some of the key electrochemical reactions, including the CO2 reduction reaction. In this context, recent research advances in the development of heterogeneous nanostructured carbon-based catalysts for electrochemical reduction of CO2 are summarized. The leading factors for consideration in carbon-based catalyst research are discussed by analyzing the main challenges faced by electrochemical reduction of CO2. Then the emerging metal-free doped carbon and aromatic N-heterocycle catalysts for electrochemical reduction of CO2 with an emphasis on the formation of multicarbon hydrocarbons and oxygenates are discussed. Following that, the recent progress in metal-nitrogen-carbon structures as an extension of carbon-based catalysts is scrutinized. Finally, an outlook for the future development of catalysts as well as the whole electrochemical system for CO2 reduction is provided.

  • 12.
    Wu, Junru
    et al.
    Institute of Materials Research, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, China; School of Materials Science and Engineering, Tsinghua University, Beijing, China.
    Gao, Ziyao
    Institute of Materials Research, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, China; School of Materials Science and Engineering, Tsinghua University, Beijing, China.
    Tian, Yao
    Institute of Materials Research, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, China.
    Zhao, Yun
    Institute of Materials Research, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, China.
    Lin, Yilong
    School of Materials Science and Engineering, Sun Yat-sen University, Guangzhou, China.
    Wang, Kang
    School of Chemistry, National and Local Joint Engineering Research Center of MPTES in High Energy and Safety LIBs, Engineering Research Center of MTEES (Ministry of Education) and Key Lab. of ETESPG(GHEI), South China Normal University, Guangzhou, China.
    Guo, Hexin
    Institute of Materials Research, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, China; School of Materials Science and Engineering, Tsinghua University, Beijing, China.
    Pan, Yanfang
    Institute of Materials Research, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, China.
    Wang, Xianshu
    National and Local Joint Engineering Research Center of Lithium-ion Batteries and Materials Preparation Technology, Key Laboratory of Advanced Battery Materials of Yunnan Province, Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming, China.
    Kang, Feiyu
    Institute of Materials Research, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, China; School of Materials Science and Engineering, Tsinghua University, Beijing, China.
    Tavajohi Hassan Kiadeh, Naser
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Fan, Xiulin
    State Key Laboratory of Silicon Materials, School of Materials Science and Engineering, Zhejiang University, Hangzhou, China.
    Li, Baohua
    Institute of Materials Research, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, China.
    Unique tridentate coordination tailored solvation sheath towards highly stable lithium metal batteries2023In: Advanced Materials, ISSN 0935-9648, E-ISSN 1521-4095, Vol. 35, no 38, article id 2303347Article in journal (Refereed)
    Abstract [en]

    Electrolyte optimization by solvent molecule design has been recognized as an effective approach for stabilizing lithium (Li) metal batteries. However, the coordination pattern of Li+ with solvent molecules has been sparsely considered. Here, we report an electrolyte design strategy based on bi/tridentate chelation of Li+ and solvent to tune the solvation structure. As a proof of concept, a novel solvent with multi oxygen coordination sites is demonstrated to facilitate the formation of an anion-aggregated solvation shell, enhancing the interfacial stability and de-solvation kinetics. As a result, the as-developed electrolyte exhibits ultra-stable cycling over 1400 h in symmetric cells with 50 ?m-thin Li foils. When paired with high-loading LiFePO4, full cells maintain 92% capacity over 500 cycles and deliver improved electrochemical performances over a wide temperature range from -10 °C to 60 °C. Furthermore, the concept is validated in a pouch cell (570 mAh), achieving a capacity retention of 99.5% after 100 cycles. This brand-new insight on electrolyte engineering provides guidelines for practical high-performance Li metal batteries. This article is protected by copyright. All rights reserved

  • 13.
    Wågberg, Thomas
    et al.
    Umeå University, Faculty of Science and Technology, Physics.
    Hania, Ralph
    Robinson, Nate
    Shin, Joon Ho
    Umeå University, Faculty of Science and Technology, Physics.
    Matyba, Piotr
    Umeå University, Faculty of Science and Technology, Physics.
    Edman, Ludvig
    Umeå University, Faculty of Science and Technology, Physics.
    On the Limited Operational Lifetime of Light-Emitting Electrochemical Cells2008In: Advanced Materials, ISSN 0935-9648, E-ISSN 1521-4095, Vol. 20, no 9, p. 1744-1749Article in journal (Refereed)
  • 14.
    Yao, Mingguang
    et al.
    State Key Laboratory of Superhard Materials, Jilin University, Changchun, China.
    Cui, Wen
    State Key Laboratory of Superhard Materials, Jilin University, Changchun, China.
    Du, Mingrun
    State Key Laboratory of Superhard Materials, Jilin University, Changchun, China.
    Xiao, Junping
    State Key Laboratory of Superhard Materials, Jilin University, Changchun, China.
    Yang, Xigui
    State Key Laboratory of Superhard Materials, Jilin University, Changchun, China.
    Liu, Shijie
    State Key Laboratory of Superhard Materials, Jilin University, Changchun, China.
    Liu, Ran
    State Key Laboratory of Superhard Materials, Jilin University, Changchun, China.
    Wang, Fei
    State Key Laboratory of Superhard Materials, Jilin University, Changchun, China.
    Cui, Tian
    State Key Laboratory of Superhard Materials, Jilin University, Changchun, China.
    Sundqvist, Bertil
    Umeå University, Faculty of Science and Technology, Department of Physics. State Key Laboratory of Superhard Materials, Jilin University, Changchun, China.
    Liu, Bingbing
    State Key Laboratory of Superhard Materials, Jilin University, Changchun, China.
    Tailoring Building Blocks and Their Boundary Interactionfor the Creation of New, Potentially Superhard, Carbon Materials2015In: Advanced Materials, ISSN 0935-9648, E-ISSN 1521-4095, Vol. 27, no 26, p. 3962-3968Article in journal (Refereed)
    Abstract [en]

    A strategy for preparing hybrid carbon structures with amorphous carbon clusters as hard building blocks by compressing a series of predesigned two-component fullerides is presented. In such constructed structures the building blocks and their boundaries can be tuned by changing the starting components, providing a way for the creation of new hard/superhard materials with desirable properties.

  • 15.
    Zhang, Xiaoying
    et al.
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Ràfols-Ribé, Joan
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Mindemark, Jonas
    Department of Chemistry − Ångström Laboratory, Uppsala University, Uppsala, Sweden.
    Tang, Shi
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Lindh, Mattias
    Sustainable Resource Conversion unit, Biorefinery and Energy department, RISE Research Institutes of Sweden AB, Storgatan 65, Umeå, Sweden.
    Gracia-Espino, Eduardo
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Larsen, Christian
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Edman, Ludvig
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Efficiency roll-off in light-emitting electrochemical cells2024In: Advanced Materials, ISSN 0935-9648, E-ISSN 1521-4095Article in journal (Refereed)
    Abstract [en]

    Understanding “efficiency roll-off” (i.e., the drop in emission efficiency with increasing current) is critical if efficient and bright emissive technologies are to be rationally designed. Emerging light-emitting electrochemical cells (LECs) can be cost- and energy-efficiently fabricated by ambient-air printing by virtue of the in situ formation of a p-n junction doping structure. However, this in situ doping transformation renders a meaningful efficiency analysis challenging. Herein, a method for separation and quantification of major LEC loss factors, notably the outcoupling efficiency and exciton quenching, is presented. Specifically, the position of the emissive p-n junction in common singlet-exciton emitting LECs is measured to shift markedly with increasing current, and the influence of this shift on the outcoupling efficiency is quantified. It is further verified that the LEC-characteristic high electrochemical-doping concentration renders singlet-polaron quenching (SPQ) significant already at low drive current density, but also that SPQ increases super-linearly with increasing current, because of increasing polaron density in the p-n junction region. This results in that SPQ dominates singlet-singlet quenching for relevant current densities, and significantly contributes to the efficiency roll-off. This method for deciphering the LEC efficiency roll-off can contribute to a rational realization of all-printed LEC devices that are efficient at highluminance.

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