129 results match your criteria spinning voltage

A new magnetic melt spinning device for patterned nanofiber.

Sci Rep 2021 Apr 26;11(1):8895. Epub 2021 Apr 26.

School of Mechanical Engineering, Sichuan University, Chengdu, 610065, China.

The size and morphology of nanofibers directly determine their application scope and performance, while regular patterned fibers further demonstrate their superior performance in the field of sensors and biomaterials. Melt electrospinning enables controlled deposition of fibers and is currently one of the most important means of preparing patterned fibers. However, due to the existence of high-voltage electric field, melt electrospinning has safety problems such as partial discharge and electric field breakdown, coupled with the charge rejection on the fiber surface, which seriously affects the positioning deposition of fibers and makes it difficult to obtain regular patterned fibers, greatly limiting the application areas and application effects of patterned fibers. Read More

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NMR Spectroscopic Studies of Ion Channels in Lipid Bilayers: Sample Preparation Strategies Exemplified by the Voltage Dependent Anion Channel.

Methods Mol Biol 2021 ;2302:201-217

Department of Chemistry, University of Florida, Gainesville, FL, USA.

We describe approaches for the preparation of membrane proteins in detergent micelles and lipid bilayers for solution and magic angle spinning NMR studies, respectively, as exemplified by the human voltage dependent anion channel 1 (hVDAC1). Here, we report protocols for the preparation of homogenous samples of recombinant hVDAC1 in detergent micelles and lipid two-dimensional crystals yielding high resolution NMR spectra. Procedures are described for the recombinant production of stable-isotope labeled hVDAC1 in E. Read More

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January 2021

Structure, gating and interactions of the voltage-dependent anion channel.

Eur Biophys J 2021 Mar 29;50(2):159-172. Epub 2021 Mar 29.

Department of NMR-Based Structural Biology, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077, Göttingen, Germany.

The voltage-dependent anion channel (VDAC) is one of the most highly abundant proteins found in the outer mitochondrial membrane, and was one of the earliest discovered. Here we review progress in understanding VDAC function with a focus on its structure, discussing various models proposed for voltage gating as well as potential drug targets to modulate the channel's function. In addition, we explore the sensitivity of VDAC structure to variations in the membrane environment, comparing DMPC-only, DMPC with cholesterol, and near-native lipid compositions, and use magic-angle spinning NMR spectroscopy to locate cholesterol on the outside of the β-barrel. Read More

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Construction of Nanocrystalline Cellulose-Based Composite Fiber Films with Excellent Porosity Performances via an Electrospinning Strategy.

ACS Omega 2021 Feb 11;6(7):4958-4967. Epub 2021 Feb 11.

State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004, P. R. China.

Cellulose nanocrystals (CNCs) not only have environmental protection characteristics of being lightweight, degradable, green, and renewable but also have some nanocharacteristics of high strength, large specific surface area, and obvious small size effect, so they are often used as a reinforcing agent in various polymers. However, the hydrogen bonding between CNC molecules is relatively strong, and they can easily aggregate and get entangled with each other. In this work, several large-porosity composite nanofiber films, KH550-CNC/waterborne polyurethane (WPU)/poly(vinyl alcohol) (PVAL) with KH550-modified CNCs, are prepared using poly(vinyl alcohol) (PVAL) solution and electrospinning technology. Read More

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February 2021

Robust Effects of Graphene Oxide on Polyurethane/Tourmaline Nanocomposite Fiber.

Polymers (Basel) 2020 Dec 23;13(1). Epub 2020 Dec 23.

Department of Biomedical Engineering, City University of Hong Kong, Kowloon, Hong Kong 999077, China.

The use of energy therapy including tourmaline/negative ions has gained huge popularity due to their long-standing historical evidence in improving human health and the technology development. However, the limitations of tourmaline based polyurethane fibers including the unsatisfied mechanical properties and negative ions releasing performances hind their further applications for wearable energy therapy. In this study, graphene oxide was modified within the polyurethane/tourmaline nanocomposite and then the wet-spinning method was used to prepare the fibers. Read More

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December 2020

Nanofibers-Based Piezoelectric Energy Harvester for Self-Powered Wearable Technologies.

Polymers (Basel) 2020 Nov 16;12(11). Epub 2020 Nov 16.

School of Electrical, Computer and Telecommunications Engineering, Faculty of Engineering and Information Sciences, University of Wollongong, Wollongong 2522, Australia.

The demands for wearable technologies continue to grow and novel approaches for powering these devices are being enabled by the advent of new energy materials and novel manufacturing strategies. In addition, decreasing the energy consumption of portable electronic devices has created a huge demand for the development of cost-effective and environment friendly alternate energy sources. Energy harvesting materials including piezoelectric polymer with its special properties make this demand possible. Read More

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November 2020

Core-Shell Nanofibers of Polyvinylidene Fluoride-based Nanocomposites as Piezoelectric Nanogenerators.

Polymers (Basel) 2020 Oct 13;12(10). Epub 2020 Oct 13.

Materials Science & Technology Program (MATS), College of Arts & Sciences, Qatar University, Doha 2713, Qatar.

Flexible piezoelectric nanogenerators (PENG) are widely applied to harvest sustainable energy from multiple energy sources. The rational and simple design of PENG have great potential in soft electronics. Here we design a highly flexible PENG using the polyvinylidene fluoride (PVDF) and its copolymer, polyvinylidene hexafluoropropylene (PVDF-HFP) with two nanoarchitectures of semiconducting metal oxides, TiO and ZnO. Read More

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October 2020

Auroral ionospheric plasma flow extraction using subsonic retarding potential analyzers.

Rev Sci Instrum 2020 Sep;91(9):094503

SRI International, Menlo Park, California 94025, USA.

Thermal ion retarding potential analyzers (RPAs) are used to measure in situ auroral ionospheric plasma parameters. This article analyzes data from a low-resource RPA in order to quantify the capability of the sensor. The RPA collects a sigmoidal current-voltage (I-V) curve, which depends on a non-linear combination of Maxwellian plasma parameters, so a forward-modeling procedure is used to match the best choice plasma parameters for each I-V curve. Read More

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September 2020

Enhancement of PVDF Sensing Characteristics by Retooling the Near-Field Direct-Write Electrospinning System.

Sensors (Basel) 2020 Aug 28;20(17). Epub 2020 Aug 28.

Department of Mechanical and Electro-Mechanical Engineering, National Sun Yat-sen University, Kaohsiung 80424, Taiwan.

This research aimed to develop a direct-write near-field electrospinning system (DW-NFES) with three-axis positioning of controllable speed, torque and position to produce sizable and high-quality piezoelectric fibers for sensing purposes. Sensor devices with high electrical response signals were developed and tested. To achieve DW-NFES purpose, a servo motor controller was designed to develop a high response rate, accurate positioning, and stable mobile device through the calculation of bandwidth and system time delay. Read More

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Direct incorporation of mesenchymal stem cells into a Nanofiber scaffold - in vitro and in vivo analysis.

Sci Rep 2020 06 12;10(1):9557. Epub 2020 Jun 12.

Center for Orthopedics and Trauma Surgery, University Hospital Giessen and Marburg, Location Marburg, Marburg, Germany.

Bony defects are a common problem in musculoskeletal surgery. Replacement with autologous bone grafts is limited by availability of transplant material. Sterilized cancellous bone, while being osteoconductive, has limited osteoinductivity. Read More

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Multicolor Electrochromic Dye-Doped Liquid Crystal Yolk-Shell Microcapsules.

ACS Appl Mater Interfaces 2020 Jul 22;12(26):29728-29736. Epub 2020 Jun 22.

Key Laboratory of Science & Technology of Eco-Textile, Jiangnan University, Ministry of Education, Wuxi, Jiangsu 214122, P.R. China.

A new system of yolk-shell microcapsules containing two types of dye-doped liquid crystals was prepared via seed emulsion polymerization in which the synthetic process was mimicking plant respiration. The resulting system demonstrated reversible low voltage-driven switching between multispectral colored and transparent states. Moreover, wearable multicolor electrochromic fibers based on calcium alginate were produced via wet spinning to expand the application of yolk-shell dye-doped liquid crystal microcapsules. Read More

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Electrospun Nano-Fibers for Biomedical and Tissue Engineering Applications: A Comprehensive Review.

Materials (Basel) 2020 May 6;13(9). Epub 2020 May 6.

Department of Mechanical and Industrial Engineering, Norwegian University of Science and Technology, 7491 Trondheim, Norway.

Pharmaceutical nano-fibers have attracted widespread attention from researchers for reasons such as adaptability of the electro-spinning process and ease of production. As a flexible method for fabricating nano-fibers, electro-spinning is extensively used. An electro-spinning unit is composed of a pump or syringe, a high voltage current supplier, a metal plate collector and a spinneret. Read More

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Magnetic-Electrospinning Synthesis of γ-FeO Nanoparticle-Embedded Flexible Nanofibrous Films for Electromagnetic Shielding.

Polymers (Basel) 2020 Mar 20;12(3). Epub 2020 Mar 20.

Collaborative Innovation Center for Nanomaterials & Devices, College of Physics, Qingdao University, Qingdao 266071, China.

The exploration of a new family of flexible and high-performance electromagnetic shielding materials is of great significance to the next generation of intelligent electronic products. In this paper, we report a simple magnetic-electrospinning (MES) method for the preparation of a magnetic flexible film, γ-FeO nanoparticle-embedded polymeric nanofibers. By introducing the extra magnetic field force on γ-FeO nanoparticles within composite fibers, the critical voltage for spinning has been reduced, along with decreased fiber diameters. Read More

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A Self-Powered Flexible Thermoelectric Sensor and Its Application on the Basis of the Hollow PEDOT:PSS Fiber.

Polymers (Basel) 2020 Mar 3;12(3). Epub 2020 Mar 3.

National Engineering Research Center for Analysis and Application of Agro-Ecological Big Data, Anhui University, No. 111 Jiulong Road, Hefei 230601, China.

The thermoelectric (TE) fiber, based on poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS), which possesses good flexibility, a low cost, good environmental stability and non-toxicity, has attracted more attention due to its promising applications in energy harvesting. This study presents a self-powered flexible sensor based on the TE properties of the hollow PEDOT:PSS fiber. The hollow structure of the fiber was synthesized using traditional wet spinning. Read More

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Design and experimental demonstration of Doppler cloak from spatiotemporally modulated metamaterials based on rotational Doppler effect.

Opt Express 2020 Feb;28(3):3745-3755

Recently, spatiotemporally modulated metamaterial has been theoretically demonstrated for the design of Doppler cloak, a technique used to cloak the motion of moving objects from the observer by compensating for the Doppler shift. Linear Doppler effect has an angular counterpart, i.e. Read More

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February 2020

Wet-spinning assembly and in situ electrodeposition of carbon nanotube-based composite fibers for high energy density wire-shaped asymmetric supercapacitor.

J Colloid Interface Sci 2020 Jun 24;569:298-306. Epub 2020 Feb 24.

Department of Mechanical Engineering, University of Delaware, Newark, DE 19716, United States. Electronic address:

Wire-shaped supercapacitors (WSC) have attracted tremendous attention for powering portable electronic devices. However, previously reported WSC suffered from a complicated fabrication process and high cost. The objective of this study is to develop a facile and scalable process for the fabrication of high energy density WSC. Read More

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Recent Progress of the Needleless Electrospinning for High Throughput of Nanofibers.

Recent Pat Nanotechnol 2019 ;13(3):164-170

School of Textile and Garment, Anhui Polytechnic University, No.8 Beijing Mid-Road, Wuhu, 241000, China.

Background: In recent decades, nanofiber-based materials have been considered as one of the top interesting fundamental materials for academic studies and practical applications. However, the electrospinning, as the most popular method for manufacturing nanofibers, is plagued by its low productivity. The first patent about electrospinning was emerged in 1934 and the needleless electrospinning is regarded as one of the most promising methods to realize the high throughput of nanofibers. Read More

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February 2020

TiCT Nanosheets/TiCT Quantum Dots/RGO (Reduced Graphene Oxide) Fibers for an All-Solid-State Asymmetric Supercapacitor with High Volume Energy Density and Good Flexibility.

ACS Appl Mater Interfaces 2020 Mar 28;12(10):11833-11842. Epub 2020 Feb 28.

Ministry of Education, Key Laboratory of Applied Surface and Colloid Chemistry, Shaanxi Normal University, Xi'an 710062, P. R. China.

By using TiCT quantum dots as interlayer spacers, TiCT nanosheets/TiCT quantum dots/RGO (reduced graphene oxide) fiber (MMRG) is prepared by a wet-spinning method; it shows good capacitance and excellent flexibility. The MMRG fiber electrode possesses a novel network structure and a maximum volumetric capacitance of 542 F cm, and its capacitance and flexibility are affected by the amount of TiCT quantum dots. Also, the TiCT/PEDOT:PSS [poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate)] fiber (MP) is prepared by injecting a homogeneous suspension of TiCT nanosheets and PEDOT:PSS into a bath of 98 wt % HSO. Read More

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Fabrication and Characterization of Electrospun Aligned Porous PAN/Graphene Composite Nanofibers.

Nanomaterials (Basel) 2019 Dec 15;9(12). Epub 2019 Dec 15.

School of Mechanical and Electric Engineering, Soochow University, Suzhou 215123, China.

A modified parallel electrode method (MPEM), conducted by placing a positively charged ring between the needle and the paralleled electrode collector, was presented to fabricate aligned polyacrylonitrile/graphene (PAN/Gr) composite nanofibers (CNFs) with nanopores in an electrospinning progress. Two kinds of solvents and one kind of nanoparticle were used to generate pores on composite nanofibers. The spinning parameters, such as the concentration of solute and solvent, spinning voltage and spinning distance were discussed, and the optimal parameters were determined. Read More

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December 2019

Multiple-Jet Needleless Electrospinning Approach via a Linear Flume Spinneret.

Polymers (Basel) 2019 Dec 11;11(12). Epub 2019 Dec 11.

School of Textile Science and Engineering, Xi'an Polytechnic University, Xi'an 710048, China.

There is a great limitation to improving the quality and productivity of nanofibers through the conventional single-needle method. Using needleless electrospinning technology to generate multiple jets and enhance the productivity of nanofibers has attracted lots of interest for many years. This study develops a novel linear flume spinneret to fabricate nanofibers. Read More

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December 2019

Blow-Spinning Enabled Precise Doping and Coating for Improving High-Voltage Lithium Cobalt Oxide Cathode Performance.

Nano Lett 2020 Jan 16;20(1):677-685. Epub 2019 Dec 16.

Division of Nanomaterials & Chemistry, Hefei National Laboratory for Physical Sciences at the Microscale , University of Science and Technology of China , Hefei , Anhui 230026 , China.

Lithium cobalt oxide (LiCoO) possesses an attractive theoretical specific capacity (274 mAh g) and high discharge voltage (∼4.2 V vs Li/Li). However, only a half of the theoretical capacity of LiCoO is available in commercialized lithium ion batteries because of the intrinsic structural instability and detrimental interface of LiCoO at the charging voltage over 4. Read More

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January 2020

Four self-made free surface electrospinning devices for high-throughput preparation of high-quality nanofibers.

Yue Fang Lan Xu

Beilstein J Nanotechnol 2019 15;10:2261-2274. Epub 2019 Nov 15.

National Engineering Laboratory for Modern Silk, College of Textile and Engineering, Soochow University, 199 Ren-ai Road, Suzhou 215123, China.

Four different self-made free surface electrospinning (FSE) techniques, namely, modified bubble-electrospinning (MBE), modified free surface electrospinning (MFSE), oblique section free surface electrospinning (OSFSE) and spherical section free surface electrospinning (SSFSE), designed for high-throughput preparation of high-quality nanofibers, are presented in this paper. The mechanisms of fiber preparation of the corresponding four FSE devices were studied by simulating the electric field distribution using the Maxwell 3D software. The properties of the electric field in the device are very important for the FSE process. Read More

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November 2019

Nuclear spin-hyperpolarization generated in a flavoprotein under illumination: experimental field-dependence and theoretical level crossing analysis.

Sci Rep 2019 12 5;9(1):18436. Epub 2019 Dec 5.

Institut für Analytische Chemie, Universität Leipzig, Linnéstr. 3, 04103, Leipzig, Germany.

The solid-state photo-chemically induced dynamic nuclear polarization (photo-CIDNP) effect generates non-equilibrium nuclear spin polarization in frozen electron-transfer proteins upon illumination and radical-pair formation. The effect can be observed in various natural photosynthetic reaction center proteins using magic-angle spinning (MAS) nuclear magnetic resonance (NMR) spectroscopy, and in a flavin-binding light-oxygen-voltage (LOV) domain of the blue-light receptor phototropin. In the latter system, a functionally instrumental cysteine has been mutated to interrupt the natural cysteine-involving photochemistry allowing for an electron transfer from a more distant tryptophan to the excited flavin mononucleotide chromophore. Read More

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December 2019

Highly Efficient Purification of Multicomponent Wastewater by Electrospinning Kidney-Bean-Skin-like Porous H-PPAN/rGO--PAO@Ag/Ag Composite Nanofibrous Membranes.

ACS Appl Mater Interfaces 2019 Dec 6;11(50):46920-46929. Epub 2019 Dec 6.

State Key Laboratory of Separation Membranes and Membrane Processes , Tianjin 300387 , China.

Due to the complexity of harmful wastewater components, environmental and multifunctional materials are required for sewage purification. In this paper, a novel kidney-bean-skin-like hydrophilic porous polyacrylonitrile/reduced graphene oxide--poly(amidoxime)-loaded Ag (H-PPAN/rGO--PAO@Ag/Ag) composite nanofiber membrane was fabricated by combining electrospinning and hydrolysis methods. The spinning solution was pumped at a rate of 0. Read More

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December 2019

Bubble Electrospinning with an Auxiliary Electrode and an Auxiliary Air Flow.

Recent Pat Nanotechnol 2020 ;14(1):42-45

National Engineering Laboratory for Modern Silk, College of Textile and Clothing Engineering, Soochow University, 199 Ren-Ai Road, Suzhou 215123, China.

Background: The patented bubble electrospinning, which is a simple and effective technique for mass-production of polymer nanofibers, has been studying extensively, but it is still under development. In the bubble electrospinning, multiple jets move from the positive electrode to the receptor, a long distance between the two electrodes is needed to guarantee complete solvent evaporation, as a result a relative high voltage is needed.

Objective: The aim of the present study is to use an auxiliary electrode and an auxiliary air flow to improve bubble electrospinning with lower voltage and higher output than those by its traditional one. Read More

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Control of binding of C molecules to the substrate by Coulomb blockade.

Sci Rep 2019 Nov 5;9(1):16017. Epub 2019 Nov 5.

School of Physics and Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN), Trinity College Dublin, Dublin 2, Ireland.

We report on a transition in a monolayer of C molecules deposited on a WO/W(110) substrate. The transition from a static state, where the molecules are rigidly bound to the surface by a coordination bond, to a state where the molecules are loosely bound to the surface by van der Waals force and rotate continuously, has been studied using scanning tunnelling microscopy (STM). The separation between the molecules and the surface increases by 1. Read More

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November 2019

Needle-disk Electrospinning: Mechanism Elucidation, Parameter Optimization and Productivity Improvement.

Recent Pat Nanotechnol 2020 ;14(1):46-55

School of Textile and Garment, Anhui Polytechnic University, No.8 Beijing Mid-Road, Wuhu, 241000, China.

Background: Nanofiber's productivity plagues nanofibrous membranes' applications in many areas. Herein, we present the needle-disk electrospinning to improve throughput. In this method, multiple high-curvature mentals are used as the spinning electrode. Read More

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Rhythmic calcium transients in smooth muscle cells of the mouse internal anal sphincter.

Neurogastroenterol Motil 2020 03 18;32(3):e13746. Epub 2019 Oct 18.

Department of Physiology and Cell Biology, University of Nevada, Reno School of Medicine, Reno, NV, USA.

Background: The internal anal sphincter (IAS) exhibits slow waves (SWs) and tone that are dependent upon L-type Ca channels (Cav ) suggesting that phasic events (ie, SWs) play a fundamental role in tone generation. The present study further examined phasic activity in the IAS by measuring the spatiotemporal properties of Ca transients (CTs) in IAS smooth muscle cells (SMCs).

Methods: Ca transients were recorded with spinning disk confocal microscopy from the IAS of SM-GCaMP mice. Read More

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Enhanced Lifetime and Photostability with Low-Temperature Mesoporous ZnTiO /Compact SnO Electrodes in Perovskite Solar Cells.

Angew Chem Int Ed Engl 2019 Dec 4;58(51):18460-18465. Epub 2019 Nov 4.

Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, China.

Perovskite solar cells (PSCs) with power conversion efficiencies (PCEs) of 25 % mainly have SnO or TiO as electron-transporting layers (ETLs). Now, zinc titanate (ZnTiO , ZTO) is proposed as mesoporous ETLs owing to its weak photo-effect, excellent carrier extraction, and transfer properties. Uniform mesoporous films were obtained by spinning coating the ZTO ink and annealed below 150 °C. Read More

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December 2019

Understanding the High Performance of over 15% Efficiency in Single-Junction Bulk Heterojunction Organic Solar Cells.

Adv Mater 2019 Nov 9;31(48):e1903868. Epub 2019 Oct 9.

Center for Polymers and Organic Solids, University of California Santa Barbara (UCSB), Santa Barbara, CA, 93106, USA.

The highly efficient single-junction bulk-heterojunction (BHJ) PM6:Y6 system can achieve high open-circuit voltages (V ) while maintaining exceptional fill-factor (FF) and short-circuit current (J ) values. With a low energetic offset, the blend system is found to exhibit radiative and non-radiative recombination losses that are among the lower reported values in the literature. Recombination and extraction dynamic studies reveal that the device shows moderate non-geminate recombination coupled with exceptional extraction throughout the relevant operating conditions. Read More

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November 2019