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Vol. 9 No. 4 (2017)

Regulating Charge and Exciton Distribution in High-Performance Hybrid White Organic Light-Emitting Diodes with n-Type Interlayer Switch

https://doi.org/10.1007/s40820-017-0138-4
Dongxiang Luo
School of Materials and Energy, Guangdong University of Technology, Guangzhou 510006, People’s Republic of China
Yanfeng Yang
School of Materials and Energy, Guangdong University of Technology, Guangzhou 510006, People’s Republic of China
Ye Xiao
School of Materials and Energy, Guangdong University of Technology, Guangzhou 510006, People’s Republic of China
Yu Zhao
School of Materials and Energy, Guangdong University of Technology, Guangzhou 510006, People’s Republic of China
Yibin Yang
School of Materials and Energy, Guangdong University of Technology, Guangzhou 510006, People’s Republic of China
Baiquan Liu
Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices, South China University of Technology, Guangzhou 510640, People’s Republic of China

Corresponding Author: Baiquan Liu

bqliu1012@gmail.com

Nano-Micro Letters, Vol. 9 No. 4 (2017), Article Number: 37

Abstract

The interlayer (IL) plays a vital role in hybrid white organic light-emitting diodes (WOLEDs); however, only a negligible amount of attention has been given to n-type ILs. Herein, the n-type IL, for the first time, has been demonstrated to achieve a high efficiency, high color rendering index (CRI), and low voltage trade-off. The device exhibits a maximum total efficiency of 41.5 lm W−1, the highest among hybrid WOLEDs with n-type ILs. In addition, high CRIs (80–88) at practical luminances (≥1000 cd m−2) have been obtained, satisfying the demand for indoor lighting. Remarkably, a CRI of 88 is the highest among hybrid WOLEDs. Moreover, the device exhibits low voltages, with a turn-on voltage of only 2.5 V (>1 cd m−2), which is the lowest among hybrid WOLEDs. The intrinsic working mechanism of the device has also been explored; in particular, the role of n-type ILs in regulating the distribution of charges and excitons has been unveiled. The findings demonstrate that the introduction of n-type ILs is effective in developing high-performance hybrid WOLEDs.


Highlights:


1 The n-type interlayer was demonstrated to achieve a high efficiency, high color rendering index (CRI), and low voltage trade-off. The device exhibits a maximum total efficiency of 41.5 lm W−1 and a low turn-on voltage of 2.5 V (>1 cd m−2).
2 High CRIs (80–88) at practical luminances (≥1000 cd m−2) were obtained, with a CRI of 88 being the highest among hybrid WOLEDs.

Keywords

White light Hybrid Interlayer Color rendering index Organic light-emitting diodes
Luo, Dongxiang, Yanfeng Yang, Ye Xiao, Yu Zhao, Yibin Yang, and Baiquan Liu. 2017. “Regulating Charge and Exciton Distribution in High-Performance Hybrid White Organic Light-Emitting Diodes With N-Type Interlayer Switch”. Nano-Micro Letters 9 (4):37. https://doi.org/10.1007/s40820-017-0138-4.
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References
  1. Q. Wang, D. Ma, Management of charges and excitons for high-performance white organic light-emitting diodes. Chem. Soc. Rev. 39(7), 2387–2398 (2010). doi:10.1039/b909057f
  2. Y. Tao, C. Yang, J. Qin, Organic host materials for phosphorescent organic light-emitting diodes. Chem. Soc. Rev. 40(5), 2943–2970 (2011). doi:10.1039/c0cs00160k
  3. H. Sasabe, J. Kido, Development of high performance OLEDs for general lighting. J. Mater. Chem. C 1(9), 1699–1707 (2013). doi:10.1039/c2tc00584k
  4. B. Liu, D. Gao, J. Wang, X. Wang, L. Wang, J. Zou, H. Ning, J. Peng, Progress of white organic light-emitting diodes. Acta Phys. Chim. Sin. 31(10), 1823–1852 (2015). doi:10.3866/PKU.WHXB201506192
  5. X. Yang, G. Zhou, W.-Y. Wong, Functionalization of phosphorescent emitters and their host materials by main-group elements for phosphorescent organic light-emitting devices. Chem. Soc. Rev. 44(23), 8484–8575 (2015). doi:10.1039/C5CS00424A
  6. S. Reineke, F. Linner, G. Schwartz, N. Seidler, K. Walzer, B. Lussem, K. Leo, White organic light-emitting diodes with fluorescent tube efficiency. Nature 459(7244), 234–238 (2009). doi:10.1038/nature08003
  7. M. Du, Y. Feng, D. Zhu, T. Peng, Y. Liu, Y. Wang, M.R. Bryce, Novel emitting system based on a multifunctional bipolar phosphor: an effective approach for highly efficient warm-white light-emitting devices with high color-rendering index at high luminance. Adv. Mater. 28(28), 5963–5968 (2016). doi:10.1002/adma.201600451
  8. C. Fan, C. Yang, Yellow/orange emissive heavy-metal complexes as phosphors in monochromatic and white organic light-emitting devices. Chem. Soc. Rev. 43(17), 6439–6469 (2014). doi:10.1039/C4CS00110A
  9. Y. Li, W. Zhang, L. Zhang, X. Wen, Y. Yin et al., Ultra-high general and special color rendering index white organic light-emitting device based on a deep red phosphorescent dye. Org. Electron. 14(12), 3201–3205 (2013). doi:10.1016/j.orgel.2013.09.035
  10. Y. Yin, J. Yu, H. Cao, L. Zhang, H. Sun, W. Xie, Efficient non-doped phosphorescent orange, blue and white organic light-emitting devices. Sci. Rep. 4, 6754 (2014). doi:10.1038/srep06754
  11. Y. Sun, N. Giebink, H. Kanno, B. Ma, M. Thompson, S.R. Forrest, Management of singlet and triplet excitons for efficient white organic light-emitting devices. Nature 440(7086), 908–912 (2006). doi:10.1038/nature04645
  12. N. Sun, Q. Wang, Y. Zhao, Y. Chen, D. Yang, F. Zhao, J. Chen, D. Ma, High-performance hybrid white organic light-emitting devices without interlayer between fluorescent and phosphorescent emissive regions. Adv. Mater. 26(10), 1617–1621 (2014). doi:10.1002/adma.201304779
  13. G. Schwartz, S. Reineke, T.C. Rosenow, K. Walzer, K. Leo, Triplet harvesting in hybrid white organic light-emitting diodes. Adv. Funct. Mater. 19(9), 1319–1333 (2009). doi:10.1002/adfm.200801503
  14. C.-J. Zheng, J. Wang, J. Ye, M.-F. Lo, X.-K. Liu, M.-K. Fung, X.-H. Zhang, C.-S. Lee, Novel efficient blue fluorophors with small singlet-triplet splitting: hosts for highly efficient fluorescence and phosphorescence hybrid WOLEDs with simplified structure. Adv. Mater. 25(15), 2205–2211 (2013). doi:10.1002/adma.201204724
  15. J. Ye, C.-J. Zheng, X.-M. Ou, X.-H. Zhang, M.-K. Fung, C.-S. Lee, Management of singlet and triplet excitons in a single emission layer: a simple approach for a high-efficiency fluorescence/phosphorescence hybrid white organic light-emitting device. Adv. Mater. 24(25), 3410–3414 (2012). doi:10.1002/adma.201201124
  16. Y. Chen, F. Zhao, Y. Zhao, J. Chen, D. Ma, Ultra-simple hybrid white organic light-emitting diodes with high efficiency and CRI trade-off: fabrication and emission-mechanism analysis. Org. Electron. 13(12), 2807–2815 (2012). doi:10.1016/j.orgel.2012.08.031
  17. B. Liu, L. Wang, Y. Gao, J. Zou, H. Ning, J. Peng, Y. Cao, Extremely high-efficiency and ultrasimplified hybrid white organic light-emitting diodes exploiting double multifunctional blue emitting layers. Light Sci. Appl. 5, e16137 (2016). doi:10.1038/lsa.2016.137
  18. D. Zhang, L. Duan, Y. Zhang, Y. Li, D. Zhang, Y. Qiu, Highly efficient and color-stable hybrid warm white organic light-emitting diodes using a blue material with thermally activated delayed fluorescence. J. Mater. Chem. C 2(38), 8191–8197 (2014). doi:10.1039/C4TC01289E
  19. D. Zhang, L. Duan, Y. Zhang, M. Cai, D. Zhang, Y. Qiu, Highly efficient hybrid warm white organic light-emitting diodes using a blue thermally activated delayed fluorescence emitter: exploiting the external heavy-atom effect. Light Sci. Appl. 4(1), 232 (2015). doi:10.1038/lsa.2015.5
  20. K. Wang, F. Zhao, C. Wang, S. Chen, D. Chen, H. Zhang, Y. Liu, D. Ma, Y. Wang, High-performance red, green, and blue electroluminescent devices based on blue emitters with small singlet-triplet splitting and ambipolar transport property. Adv. Funct. Mater. 23(21), 2672–2680 (2013). doi:10.1007/978-3-642-33596-9
  21. B.S. Kim, K.S. Yook, J.Y. Lee, Above 20% external quantum efficiency in novel hybrid white organic light-emitting diodes having green thermally activated delayed fluorescent emitter. Sci. Rep. 4, 6019 (2014). doi:10.1038/srep06019
  22. C.-L. Ho, W.-Y. Wong, Q. Wang, D. Ma, L. Wang, Z. Lin, A multifunctional iridium-carbazolyl orange phosphor for high-performance two-element WOLED exploiting exciton-managed fluorescence/phosphorescence. Adv. Funct. Mater. 18(18), 928–937 (2008). doi:10.1002/adfm.200701115
  23. B. Liu, M. Xu, L. Wang, X. Yan, H. Tao et al., Investigation and optimization of each organic layer: a simple but effective approach towards achieving high-efficiency hybrid white organic light-emitting diodes. Org. Electron. 15(4), 926–936 (2014). doi:10.1016/j.orgel.2014.02.005
  24. T. Zhang, S.-J. He, D.-K. Wang, N. Jiang, Z.-H. Lu, A multi-zoned white organic light-emitting diode with high CRI and low color temperature. Sci. Rep. 6, 20517 (2016). doi:10.1038/srep20517
  25. G. Schwartz, K. Fehse, M. Pfeiffer, K. Walzer, K. Leo, Highly efficient white organic light emitting diodes comprising an interlayer to separate fluorescent and phosphorescent regions. Appl. Phys. Lett. 89(8), 083509 (2006). doi:10.1063/1.2338588
  26. G. Schwartz, S. Reineke, K. Walzer, K. Leo, Reduced efficiency roll-off in high-efficiency hybrid white organic light-emitting diodes. Appl. Phys. Lett. 92(5), 053311 (2008). doi:10.1063/1.2836772
  27. F. Zhao, N. Sun, H. Zhang, J. Chen, D. Ma, Hybrid white organic light-emitting diodes with a double light-emitting layer structure for high color-rendering index. J. Appl. Lett. 112(8), 084504 (2012). doi:10.1063/1.4759045
  28. F. Zhao, Z. Zhang, Y. Liu, Y. Dai, J. Chen, D. Ma, A hybrid white organic light-emitting diode with stable color and reduced efficiency roll-off by using a bipolar charge carrier switch. Org. Electron. 13(6), 1049–1055 (2012). doi:10.1016/j.orgel.2012.03.005
  29. B. Liu, M. Xu, L. Wang, Y. Su, D. Gao et al., High-performance hybrid white organic light-emitting diodes comprising ultrathin blue and orange emissive layers. Appl. Phys. Express 6(12), 122201 (2013). doi:10.7567/APEX.6.122101
  30. Q. Wang, C.-L. Ho, Y. Zhao, D. Ma, W.-Y. Wong, L. Wang, Reduced efficiency roll-off in highly efficient and color-stable hybrid WOLEDs: the influence of triplet transfer and charge-transport behavior on enhancing device performance. Org. Electron. 11(2), 238–246 (2010). doi:10.1016/j.orgel.2009.11.001
  31. B. Liu, H. Nie, X. Zhou, S. Hu, D. Luo et al., Manipulation of charge and exciton distribution based on blue aggregation-induced emission fluorophors: a novel concept to achieve high-performance hybrid white organic light-emitting diodes. Adv. Funct. Mater. 26(5), 776 (2016). doi:10.1002/adfm.201503368
  32. C.-L. Ho, M.F. Lin, W.-Y. Wong, W.K. Wong, C.H. Chen, High-efficiency and color-stable white organic light-emitting devices based on sky blue electrofluorescence and orange electrophosphorescence. Appl. Phys. Lett. 92(8), 083301–083303 (2008). doi:10.1063/1.2883935
  33. Z.Y. Xia, J.H. Su, C.S. Chang, C.H. Chen, Hybrid white organic light-emitting devices based on phosphorescent iridium–benzotriazole orange–red and fluorescent blue emitters. J. Lumin. 135(135), 323–326 (2013). doi:10.1016/j.jlumin.2012.09.017
  34. B. Liu, L. Wang, M. Xu, H. Tao, J. Zou et al., Efficient hybrid white organic light-emitting diodes with extremely long lifetime: the effect of n-type interlayer. Sci. Rep. 4(4), 7198-71 (2014). doi:10.1038/srep07198
  35. P. Tao, W.-L. Li, J. Zhang, S. Guo, Q. Zhao et al., Facile synthesis of highly efficient lepidine-based phosphorescent Iridium(III) complexes for yellow and white organic light-emitting diodes. Adv. Fuct. Mater. 26(6), 881–894 (2016). doi:10.1002/adfm.201503826
  36. B. Liu, J. Zou, Z. Zhou, L. Wang, M. Xu et al., Efficient single-emitting layer hybrid white organic light-emitting diodes with low efficiency roll-off, stable color and extremely high luminance. J. Ind. Eng. Chem. 30, 85–91 (2015). doi:10.1016/j.jiec.2015.05.006
  37. C. Wu, S. Tao, M. Chen, H.W. Mo, T.W. Ng et al., A new multifunctional fluorenylcarbazole hybrid for high performance deep blue fluorescence, orange phosphorescent host and fluorescence/phosphorescence white OLEDs. Dyes Pigments 97(2), 273–277 (2013). doi:10.1016/j.dyepig.2012.12.028
  38. X.H. Yang, S.J. Zheng, H.S. Chae, S. Li, A. Mochizuki, G.E. Jabbour, Fluorescent deep-blue and hybrid white emitting devices based on a naphthalene–benzofuran compound. Org. Electron. 14(8), 2023–2028 (2013). doi:10.1016/j.orgel.2013.03.012
  39. A. Poloek, C.-T. Chen, C.-T. Chen, High performance hybrid white and multi-colour electroluminescence from a new host material for a heteroleptic naphthyridinolate platinum complex dopant. J. Mater. Chem. C 2(8), 1376–1380 (2014). doi:10.1039/c3tc32394c
  40. B. Liu, M. Xu, L. Wang, H. Tao, Y. Su et al., Very-high color rendering index hybrid white organic light-emitting diodes with double emitting nanolayers. Nano-Micro Lett. 6(4), 335–339 (2014). doi:10.1007/s40820-014-0006-4
  41. M.V.M. Rao, Y.K. Su, T.S. Huang, Y.C. Chen, White organic light emitting devices based on multiple emissive nanolayers. Nano-Micro Lett. 2(4), 242–246 (2010). doi:10.1007/BF03353850
  42. J. Yu, Y. Yin, W. Liu, W. Zhang, L. Zhang, W. Xie, H. Zhao, Effect of the greenish-yellow emission on the color rendering index of white organic light-emitting devices. Org. Electron. 15(11), 2817–2821 (2014). doi:10.1016/j.orgel.2014.08.016
  43. Z. Zhang, P. Yan, S. Yue, Y. Chen, Q. Wu et al., Low driving voltage white organic light-emitting diodes with high efficiency and low efficiency roll-off. Org. Electron. 14(9), 2172–2176 (2013). doi:10.1016/j.orgel.2013.05.024
  44. J. Chen, F. Zhao, D. Ma, Hybrid white OLEDs with fluorophors and phosphors. Mater. Today 17(4), 175–183 (2014). doi:10.1016/j.mattod.2014.04.002
  45. T. Peng, G. Li, K. Ye, C. Wang, S. Zhao, Y. Liu, Z. Hou, Y. Wang, Highly efficient phosphorescent OLEDs with host independent and concentration-insensitive properties based on a bipolar iridium complex. J. Mater. Chem. C 1(16), 2920–2926 (2013). doi:10.1039/c3tc00500c
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