Tailoring spin mixtures by ion-enhanced Maxwell magnetic coupling in color-tunable organic electroluminescent devices

Junwei Xu; Yue Cui; Gregory M. Smith; Peiyun Li; Chaochao Dun; Linqi Shao; Yang Guo; Hongzhi Wang; Yonghua Chen; David L. Carroll

doi:10.1038/s41377-018-0046-5

Go to Nature Website

Your Location：

Home >

Browse articles >

Tailoring spin mixtures by ion-enhanced Maxwell magnetic coupling in color-tunable organic electroluminescent devices

Original Articles

- Tailoring spin mixtures by ion-enhanced Maxwell magnetic coupling in color-tunable organic electroluminescent devices
- Light: Science & Applications Vol. 7, Issue 5, Pages: 454-465(2018)
- Affiliations：
  
  1.Center for Nanotechnology and Molecular Materials, Wake Forest University, Winston-Salem, NC, 27109, USA
  2.Department of Physics, Wake Forest University, Winston-Salem, NC, 27106, USA
  3.Key Laboratory of Luminescence and Optical Information (Ministry of Education), Institute of Optoelectronics Technology, Beijing Jiaotong University, 100044, Beijing, P.R. China
  4.Department of Electro-Optics, School of Engineering, University of Dayton, Dayton, OH, 45469, USA
  5.Department of Mathematics, Wake Forest University, Winston-Salem, NC, 27106, USA
  6.State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, 201620, Shanghai, P.R. China
  7.College of Materials Science and Engineering, Donghua University, 201620, Shanghai, P.R. China
  8.Institute of Advanced Materials, Nanjing Tech University, 211816, Nanjing, Jiangsu, P.R. China
  9.Present address: Department of Physics and Astronomy, College of Charleston, Charleston, SC, 29424, USA
- Author bio：
  
  David L. Carroll (carroldl@wfu.edu)
- Funds：
- DOI：10.1038/s41377-018-0046-5
  CLC：
Scan for full text
Xu, J. W. et al. Tailoring spin mixtures by ion-enhanced Maxwell magnetic coupling in color-tunable organic electroluminescent devices. Light: Science & Applications, 7, 454-465 (2018).
DOI：

Xu, J. W. et al. Tailoring spin mixtures by ion-enhanced Maxwell magnetic coupling in color-tunable organic electroluminescent devices. Light: Science & Applications, 7, 454-465 (2018). DOI： 10.1038/s41377-018-0046-5.

摘要

Abstract

In this work, we show that the spin dynamics of excitons can be dramatically altered by Maxwell magnetic field coupling, together with an ion-enhanced, low-internal-splitting-energy organic semiconducting emitter. By employing a unique, alternating current (AC)-driven organic electroluminescent (OEL) device architecture that optimizes this magnetic field coupling, almost complete control over the singlet-to-triplet ratio (from fluorescent to phosphorescent emission in a single device) is realized. We attribute this spin population control to magnetically sensitive polaron–spin pair intersystem crossings (ISCs) that can be directly manipulated through external driving conditions. As an illustration of the utility of this approach to spin-tailoring, we demonstrate a simple hybrid (double-layer) fluorescence–phosphorescence (F–P) device using a polyfluorene-based emitter with a strong external Zeeman effect and ion-induced long carrier diffusion. Remarkable control over de-excitation pathways is achieved by controlling the device-driving frequency, resulting in complete emission blue–red color tunability. Picosecond photoluminescence (PL) spectroscopy directly confirms that this color control derives from the magnetic manipulation of the singlet-to-triplet ratios. These results may pave the way to far more exotic organic devices with magnetic-field-coupled organic systems that are poised to usher in an era of dynamic spintronics at room temperature.

关键词

Keywords

references

Tang, C. W. & VanSlyke, S. A. Organic electroluminescent diodes. Appl. Phys. Lett. 51, 913–915 (1987).

Friend, R. H. et al. Electroluminescence in conjugated polymers. Nature 397, 121–128 (1999).

Pope, M., Kallmann, H. P. & Magnante, P. Electroluminescence in organic crystals. J. Chem. Phys. 38, 2042–2043 (1963).

Baldo, M. A., O'Brien, D. F., Thompson, M. E. & Forrest, S. R. Excitonic singlet-triplet ratio in a semiconducting organic thin film. Phys. Rev. B 60, 14422–14428 (1999).

Adachi, C., Baldo, M. A., Thompson, M. E. & Forrest, S. R. Nearly 100% internal phosphorescence efficiency in an organic light-emitting device. J. Appl. Phys. 90, 5048–5051 (2001).

Baldo, M. A. et al. Highly efficient phosphorescent emission from organic electroluminescent devices. Nature 395, 151–154 (1998).

Kawamura, Y. et al. 100% phosphorescence quantum efficiency of Ir(Ⅲ) complexes in organic semiconductor films. Appl. Phys. Lett. 86, 071104 (2005).

Forget, S. & Chénais, S. Organic Solid-State Lasers (Springer, Berlin, Heidelberg, 2013).

Bobbert, P. A. Manipulating spin in organic spintronics. Science 345, 1450–1451 (2014).

Hu, B. & Wu, Y. Tuning magnetoresistance between positive and negative values in organic semiconductors. Nat. Mater. 6, 985–991 (2007).

Nguyen, T. D., Gautam, B. R., Ehrenfreund, E. & Vardeny, Z. V. Magnetoconductance response in unipolar and bipolar organic diodes at ultrasmall fields. Phys. Rev. Lett. 105, 166804 (2010).

Bobbert, P. A., Nguyen, T. D., van Oost, F. W. A., Koopmans, B. & Wohlgenannt, M. Bipolaron mechanism for organic magnetoresistance. Phys. Rev. Lett. 99, 216801 (2007).

Wu, Y., Xu, Z. H., Hu, B. & Howe, J. Tuning magnetoresistance and magnetic-field-dependent electroluminescence through mixing a strong-spin-orbital-coupling molecule and a weak-spin-orbital-coupling polymer. Phys. Rev. B 75, 035214 (2007).

Mahato, R. N. et al. Ultrahigh magnetoresistance at room temperature in molecular wires. Science 341, 257–260 (2013).

Prigodin, V. N., Bergeson, J. D., Lincoln, D. M. & Epstein, A. J. Anomalous room temperature magnetoresistance in organic semiconductors. Synth. Met. 156, 757–761 (2006).

Janssen, P. et al. Tuning organic magnetoresistance in polymer-fullerene blends by controlling spin reaction pathways.Nat. Commun. 4, 2286 (2013).

Kalinowski, J., Szmytkowski, J. & Stampor, W. Magnetic hyperfine modulation of charge photogeneration in solid films of Alq3. Chem. Phys. Lett. 378, 380–387 (2003).

Wilkinson, J., Davis, A. H., Bussmann, K. & Long, J. P. Evidence for charge-carrier mediated magnetic-field modulation of electroluminescence in organic light-emitting diodes. Appl. Phys. Lett. 86, 111109 (2005).

Müller, J. G. et al. Ultrafast dynamics of charge carrier photogeneration and geminate recombination in conjugated polymer: fullerene solar cells. Phys. Rev. B 72, 195208 (2005).

Szmytkowski, J., Stampor, W., Kalinowski, J. & Kafafi, Z. H. Electric field-assisted dissociation of singlet excitons in tris-(8-hydroxyquinolinato) aluminum (Ⅲ). Appl. Phys. Lett. 80, 1465 (2002).

Stampor, W. Electromodulation of fluorescence in hole-transporting materials (TPD, TAPC) for organic light-emitting diodes. Chem. Phys. 256, 351–362 (2000).

Kalinowski, J. et al. Coexistence of dissociation and annihilation of excitons on charge carriers in organic phosphorescent emitters. Phys. Rev. B 74, 085316 (2006).

Wittmer, M. & Zschokke-Gränacher, I. Exciton–charge carrier interactions in the electroluminescence of crystalline anthracene. J. Chem. Phys. 63, 4187–4194 (1975).

Tolstov, I. V. et al. On the role of magnetic field spin effect in photoconductivity of composite films of MEH-PPV and nanosized particles of PbS. J. Lumin. 112, 368–371 (2005).

Levinson, J., Weisz, S. Z., Cobas, A. & Rolón, A. Determination of the triplet exciton-trapped electron interaction rate constant in anthracene crystals. J. Chem. Phys. 52, 2794–2795 (1970).

Shen, Z. L., Burrows, P. E., Bulović, V., Forrest, S. R. & Thompson, M. E. Three-color, tunable, organic light-emitting devices. Science 276, 2009–2011 (1997).

Fröbel, M. et al. Get it white: color-tunable AC/DC OLEDs. Light Sci. Appl. 4, e247 (2015).

Berggren, M. et al. Light-emitting diodes with variable colours from polymer blends. Nature 372, 444–446 (1994).

Al Attar, H. A., Monkman, A. P., Tavasli, M., Bettington, S. & Bryce, M. R. White polymeric light-emitting diode based on a fluorene polymer/Ir complex blend system. Appl. Phys. Lett. 86, 121101 (2005).

Parthasarathy, G., Gu, G. & Forrest, S. R. A full-color transparent metal-free stacked organic light emitting device with simplified pixel biasing. Adv. Mater. 11, 907–910 (1999).

Xu, J. W., Carroll, D. L., Smith, G. M., Dun, C. C. & Cui, Y. Achieving high performance in AC-field driven organic light sources. Sci. Rep. 6, 24116 (2016).

Xu, J. W. et al. Layered, nanonetwork composite cathodes for flexible, high-efficiency, organic light emitting devices. Adv. Funct. Mater. 25, 4397–4404 (2015).

Chen, Y. H., Xia, Y. D., Smith, G. M. & Carroll, D. L. Frequency-dependent, alternating current-driven, field-induced polymer electroluminescent devices with high power efficiency. Adv. Mater. 26, 8133–8140 (2014).

Perumal, A. et al. Novel approach for alternating current (AC)-driven organic light-emitting devices. Adv. Funct. Mater. 22, 210–217 (2012).

Tian, Y., Xu, X. J., Wang, J. S., Yao, C. & Li, L. D. Solution-processed white organic light-emitting diodes with enhanced efficiency by using quaternary ammonium salt doped conjugated polyelectrolyte. ACS Appl. Mater. Interfaces 6, 8631–8638 (2014).

Huang, F., Wu, H. B., Wang, D. L., Yang, W. & Cao, Y. Novel electroluminescent conjugated polyelectrolytes based on polyfluorene. Chem. Mater. 16, 708–716 (2004).

Khramtchenkov, D. V., Arkhipov, V. I. & Bässler, H. Charge carrier recombination in organic bilayer electroluminescent diodes. I. Theory. J. Appl. Phys. 81, 6954–6962 (1997).

Jonda, C. & Mayer, A. B. R. Investigation of the electronic properties of organic light-emitting devices by impedance spectroscopy. Chem. Mater. 11, 2429–2435 (1999).

Pingree, L. S. C., Scott, B. J., Russell, M. T., Marks, T. J. & Hersam, M. C. Negative capacitance in organic light-emitting diodes. Appl. Phys. Lett. 86, 073509 (2005).

Luo, H. W. et al. Remarkable enhancement of charge carrier mobility of conjugated polymer field-effect transistors upon incorporating an ionic additive. Sci. Adv. 2, e1600076 (2016).

Wang, J. P., Chepelianskii, A., Gao, F. & Greenham, N. C. Control of exciton spin statistics through spin polarization in organic optoelectronic devices. Nat. Commun. 3, 1191 (2012).

Cohen, A. E. Nanomagnetic control of intersystem crossing. J. Phys. Chem. A 113, 11084–11092 (2009).

Manolopoulos, D. E. & Hore, P. J. An improved semiclassical theory of radical pair recombination reactions. J. Chem. Phys. 139, 124106 (2013).

Thomas, J. K. Excited states and reactions in liquids. Ann. Rev. Phys. Chem. 21, 17–38 (1970).

Ding, B. F. et al. Magnetic field modulated exciton generation in organic semiconductors: an intermolecular quantum correlated effect. Phys. Rev. B 82, 205209 (2010).

Song, J. Y., Stingelin, N., Drew, A. J., Kreouzis, T. & Gillin, W. P. Effect of excited states and applied magnetic fields on the measured hole mobility in an organic semiconductor. Phys. Rev. B 82, 085205 (2010).

Caruntu, D., Caruntu, G. & O'Connor, C. J. Magnetic properties of variable-sized Fe 3O4 nanoparticles synthesized from non-aqueous homogeneous solutions of polyols. J. Phys. D Appl. Phys. 40, 5801–5809 (2007).

Goya, G. F. et al. Magnetic hyperthermia with Fe3O4 nanoparticles: the influence of particle size on energy absorption. IEEE Trans. Magn. 44, 4444–4447 (2008).

Iida, H., Takayanagi, K., Nakanishi, T. & Osaka, T. Synthesis of Fe 3O4 nanoparticles with various sizes and magnetic properties by controlled hydrolysis. J. Colloid Interface Sci. 314, 274–280 (2007).

Views

Downloads

CSCD

Alert me when the article has been cited

Submit

Tools

Publicity Resources

No data

Related Author

No data

Related Institution

No data

⁰