Nano Research

, Volume 10, Issue 9, pp 3077–3091 | Cite as

Curved copper nanowires-based robust flexible transparent electrodes via all-solution approach

  • Zhenxing Yin
  • Seung Keun Song
  • Sanghun Cho
  • Duck-Jae You
  • Jeeyoung Yoo
  • Suk Tai Chang
  • Youn Sang Kim
Research Article


Curved Cu nanowire (CCN)-based high-performance flexible transparent conductive electrodes (FTCEs) were fabricated via a fully solution-processed approach, involving synthesis, coating, patterning, welding, and transfer. Each step involved an innovative technique for completing the all-solution processes. The high-quality and well-dispersed CCNs were synthesized using a multi-polyol method through the synergistic effect of specific polyol reduction. To precisely control the optoelectrical properties of the FTCEs, the CCNs were uniformly coated on a polyimide (PI) substrate via a simple meniscus-dragging deposition method by tuning several coating parameters. We also employed a polyurethane (PU)-stamped patterning method to effectively produce 20 μm patterns on CCN thin films. The CCN thin films exhibited high electrical performance, which is attributed to the deeply percolated CCN network formed via a solvent-dipped welding method. Finally, the CCN thin films on the PI substrate were partially embedded and transferred to the PU matrix to reduce their surface roughness. Through consecutive processes involving the proposed methods, a highly percolated CCN thin film on the PU matrix exhibited high optoelectrical performance (R s = 53.48 Ω/□ at T = 85.71%), excellent mechanical properties (R/R 0 < 1.10 after the 10th repetition of tape peeling or 1,000 bending cycles), and a low root-mean-square surface roughness (R rms = 14.36 nm).


curved Cu nanowires all-solution processes 20 μm patterns high performance transparent electrode 


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This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIP, Ministry of Science, ICT & Future Planning) (Nos. 2016R1A2B4012992, 2016R1C1B2013145 and 2016M3A7B4910458).

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Curved copper nanowires-based robust flexible transparent electrodes via all-solution approach


  1. [1]
    Ye, S. R.; Rathmell, A. R.; Chen, Z. F.; Stewart, I. E.; Wiley, B. J. Metal nanowire networks: The next generation of transparent conductors. Adv. Mater. 2014, 26, 6670–6687.CrossRefGoogle Scholar
  2. [2]
    Zhong, Z. Y.; Woo, K.; Kim, I.; Hwang, H.; Kwon, S.; Choi, Y. M.; Lee, Y.; Lee, T. M.; Kim, K.; Moon, J. Rollto- roll-compatible, flexible, transparent electrodes based on self-nanoembedded Cu nanowires using intense pulsed light irradiation. Nanoscale 2016, 8, 8995–9003.CrossRefGoogle Scholar
  3. [3]
    Lee, J.; Lee, P.; Lee, H. B.; Hong, S. K.; Lee, I.; Yeo, J.; Lee, S. S.; Kim, T. S.; Lee, D. J.; Ko, S. H. Roomtemperature nanosoldering of a very long metal nanowire network by conducting-polymer-assisted joining for a flexible touch-panel application. Adv. Funct. Mater. 2013, 23, 4171–4176.CrossRefGoogle Scholar
  4. [4]
    Mayousse, C.; Celle, C.; Carella, A.; Simonato, J.-P. Synthesis and purification of long copper nanowires. application to high performance flexible transparent electrodes with and without PEDOT:PSS. Nano Res. 2014, 7, 315–324.CrossRefGoogle Scholar
  5. [5]
    Li, S. J.; Chen, Y. Y.; Huang, L. J.; Pan, D. C. Large-scale synthesis of well-dispersed copper nanowires in an electric pressure cooker and their application in transparent and conductive networks. Inorg. Chem. 2014, 53, 4440–4444.CrossRefGoogle Scholar
  6. [6]
    Hecht, D. S.; Hu, L. B.; Irvin, G. Emerging transparent electrodes based on thin films of carbon nanotubes, graphene, and metallic nanostructures. Adv. Mater. 2011, 23, 1482–1513.CrossRefGoogle Scholar
  7. [7]
    Lee, J. H.; Shin, D. W.; Makotchenko, V. G.; Nazarov, A. S.; Fedorov, V. E.; Kim, Y. H.; Choi, J. Y.; Kim, J. M.; Yoo, J. B. One-step exfoliation synthesis of easily soluble graphite and transparent conducting graphene sheets. Adv. Mater. 2009, 21, 4383–4387.CrossRefGoogle Scholar
  8. [8]
    Zhang, W.; Yin, Z. X.; Chun, A.; Yoo, J.; Kim, Y. S.; Piao, Y. Z. Bridging oriented copper nanowire-graphene composites for solution-processable, annealing-free, and air-stable flexible electrodes. ACS Appl. Mater. Interfaces 2016, 8, 1733–1741.CrossRefGoogle Scholar
  9. [9]
    Robinson, J. T.; Perkins, F. K.; Snow, E. S.; Wei, Z. Q.; Sheehan, P. E. Reduced graphene oxide molecular sensors. Nano Lett. 2008, 8, 3137–3140.CrossRefGoogle Scholar
  10. [10]
    Pham, D. T.; Lee, T. H.; Luong, D. H.; Yao, F.; Ghosh, A.; Le, V. T.; Kim, T. H.; Li, B.; Chang, J.; Lee, Y. H. Carbon nanotube-bridged graphene 3D building blocks for ultrafast compact supercapacitors. ACS Nano 2015, 9, 2018–2027.CrossRefGoogle Scholar
  11. [11]
    Peng, H. J.; Huang, J. Q.; Zhao, M. Q.; Zhang, Q.; Cheng, X. B.; Liu, X. Y.; Qian, W. Z.; Wei, F. Nanoarchitectured graphene/CNT@porous carbon with extraordinary electrical conductivity and interconnected micro/mesopores for lithiumsulfur batteries. Adv. Funct. Mater. 2014, 24, 2772–2781.CrossRefGoogle Scholar
  12. [12]
    Kim, Y.; Ryu, T. I.; Ok, K.-H.; Kwak, M.-G.; Park, S.; Park, N.-G.; Han, C. J.; Kim, B. S.; Ko, M. J.; Son, H. J. et al. Inverted layer-by-layer fabrication of an ultraflexible and transparent Ag nanowire/conductive polymer composite electrode for use in high-performance organic solar cells. Adv. Funct. Mater. 2015, 25, 4580–4589.CrossRefGoogle Scholar
  13. [13]
    Han, S.; Hong, S.; Ham, J.; Yeo, J.; Lee, J.; Kang, B.; Lee, P.; Kwon, J.; Lee, S. S.; Yang, M.-Y. et al. Fast plasmonic laser nanowelding for a Cu-nanowire percolation network for flexible transparent conductors and stretchable electronics. Adv. Mater. 2014, 26, 5808–5814.CrossRefGoogle Scholar
  14. [14]
    Im, H.-G.; Jung, S.-H.; Jin, J.; Lee, D.; Lee, J.; Lee, D.; Lee, J.-Y.; Kim, I.-D.; Bae, B.-S. Flexible transparent conducting hybrid film using a surface-embedded copper nanowire network: A highly oxidation-resistant copper nanowire electrode for flexible optoelectronics. ACS Nano 2014, 8, 10973–10979.CrossRefGoogle Scholar
  15. [15]
    Hu, W. L.; Wang, R. R.; Lu, Y. F.; Pei, Q. B. An elastomeric transparent composite electrode based on copper nanowires and polyurethane. J. Mater. Chem. C 2014, 2, 1298–1305.CrossRefGoogle Scholar
  16. [16]
    Nam, S.; Song, M.; Kim, D.-H.; Cho, B.; Lee, H. M.; Kwon, J.-D.; Park, S.-G.; Nam, K.-S.; Jeong, Y.; Kwon, S.-H. et al. Ultrasmooth, extremely deformable and shape recoverable Ag nanowire embedded transparent electrode. Sci. Rep. 2014, 4, 4788.CrossRefGoogle Scholar
  17. [17]
    Rathmell, A. R.; Wiley, B. J. The synthesis and coating of long, thin copper nanowires to make flexible, transparent conducting films on plastic substrates. Adv. Mater. 2011, 23, 4798–4803.CrossRefGoogle Scholar
  18. [18]
    Chu, C. R.; Lee, C.; Koo, J.; Lee, H. M. Fabrication of sintering-free flexible copper nanowire/polymer composite transparent electrodes with enhanced chemical and mechanical stability. Nano Res. 2016, 9, 2162–2173.CrossRefGoogle Scholar
  19. [19]
    Yin, Z. X.; Song, S. K.; You, D. J.; Ko, Y.; Cho, S.; Yoo, J.; Park, S. Y.; Piao, Y. Z.; Chang, S. T.; Kim, Y. S. Novel synthesis, coating, and networking of curved copper nanowires for flexible transparent conductive electrodes. Small 2015, 11, 4576–4583.CrossRefGoogle Scholar
  20. [20]
    Ding, S.; Jiu, J. T.; Gao, Y.; Tian, Y. H.; Araki, T.; Sugahara, T.; Nagao, S.; Nogi, M.; Koga, H.; Suganuma, H. et al. One-step fabrication of stretchable copper nanowire conductors by a fast photonic sintering technique and its application in wearable devices. ACS Appl. Mater. Interfaces 2016, 8, 6190–6199.CrossRefGoogle Scholar
  21. [21]
    Zhang, D. Q.; Wang, R. R.; Wen, M. C.; Weng, D.; Cui, X.; Sun, J.; Li, H. X.; Lu, Y. F. Synthesis of ultralong copper nanowires for high-performance transparent electrodes. J. Am. Chem. Soc. 2012, 134, 14283–14286.CrossRefGoogle Scholar
  22. [22]
    Yin, Z. X.; Lee, C.; Cho, S.; Yoo, J.; Piao, Y. Z.; Kim, Y. S. Facile synthesis of oxidation-resistant copper nanowires toward solution-processable, flexible, foldable, and free-standing electrodes. Small 2014, 10, 5047–5052.Google Scholar
  23. [23]
    Guo, H. Z.; Chen, Y. Z.; Ping, H. M.; Jin, J. R.; Peng, D.-L. Facile synthesis of Cu and Cu@Cu–Ni nanocubes and nanowires in hydrophobic solution in the presence of nickel and chloride ions. Nanoscale 2013, 5, 2394–2402.CrossRefGoogle Scholar
  24. [24]
    Guo, H. Z.; Chen, Y. Z.; Cortie, M. B.; Liu, X.; Xie, Q. S.; Wang, X.; Peng, D.-L. Shape-selective formation of monodisperse copper nanospheres and nanocubes via disproportionation reaction route and their optical properties. J. Phys. Chem. C 2014, 118, 9801–9808.CrossRefGoogle Scholar
  25. [25]
    Zhan, Y. J.; Lu, Y.; Peng, C.; Lou, J. Solvothermal synthesis and mechanical characterization of single crystalline copper nanorings. J. Cryst. Growth 2011, 325, 76–80.CrossRefGoogle Scholar
  26. [26]
    Zhou, L.; Fu, X.-F.; Yu, L.; Zhang, X.; Yu, X.-F.; Hao, Z.-H. Crystal structure and optical properties of silver nanorings. Appl. Phys. Lett. 2009, 94, 153102.CrossRefGoogle Scholar
  27. [27]
    Bhanushali, S.; Ghosh, P.; Ganesh, A.; Cheng, W. L. 1D copper nanostructures: Progress, challenges and opportunities. Small 2015, 11, 1232–1252.CrossRefGoogle Scholar
  28. [28]
    Rathmell, A. R.; Nguyen, M.; Chi, M. F.; Wiley, B. J. Synthesis of oxidation-resistant cupronickel nanowires for transparent conducting nanowire networks. Nano Lett. 2012, 12, 3193–3199.CrossRefGoogle Scholar
  29. [29]
    Christensen, G.; Younes, H.; Hong, H. P.; Smith, P. Effects of solvent hydrogen bonding, viscosity, and polarity on the dispersion and alignment of nanofluids containing Fe2O3 nanoparticles. J. Appl. Phys. 2015, 118, 214302.CrossRefGoogle Scholar
  30. [30]
    Ko, Y.; Song, S. K.; Kim, N. H.; Chang, S. T. Highly transparent and stretchable conductors based on a directional arrangement of silver nanowires by a microliter-scale solution process. Langmuir 2016, 32, 366–373.CrossRefGoogle Scholar
  31. [31]
    Ko, Y. U.; Cho, S. R.; Choi, K. S.; Park, Y.; Kim, S. T.; Kim, N. H.; Kim, S. Y.; Chang, S. T. Microlitre scale solution processing for controlled, rapid fabrication of chemically derived graphene thin films. J. Mater. Chem. 2012, 22, 3606–3613.CrossRefGoogle Scholar
  32. [32]
    Hu, L. B.; Kim, H. S.; Lee, J. Y.; Peumans, P.; Cui, Y. Scalable coating and properties of transparent, flexible, silver nanowire electrodes. ACS Nano 2010, 4, 2955–2963.CrossRefGoogle Scholar
  33. [33]
    Kitano, T.; Maeda, Y.; Akasaka, T. Preparation of transparent and conductive thin films of carbon nanotubes using a spreading/coating technique. Carbon 2009, 47, 3559–3565.CrossRefGoogle Scholar
  34. [34]
    Park, S.; Pitner, G.; Giri, G.; Koo, J. H.; Park, J.; Kim, K.; Wang, H. L.; Sinclair, R.; Wong, H. S. P.; Bao, Z. Large-area assembly of densely aligned single-walled carbon nanotubes using solution shearing and their application to field-effect transistors. Adv. Mater. 2015, 27, 2656–2662.CrossRefGoogle Scholar
  35. [35]
    Choi, D. Y.; Kang, H. W.; Sung, H. J.; Kim, S. S. Annealingfree, flexible silver nanowire-polymer composite electrodes via a continuous two-step spray-coating method. Nanoscale 2013, 5, 977–983.CrossRefGoogle Scholar
  36. [36]
    Jang, E. Y.; Kang, T. J.; Im, H. W.; Kim, D. W.; Kim, Y. H. Single-walled carbon-nanotube networks on large-area glass substrate by the dip-coating method. Small 2008, 4, 2255–2261.CrossRefGoogle Scholar
  37. [37]
    Duan, S. K.; Niu, Q. L.; Wei, J. F.; He, J. B.; Yin, Y. A.; Zhang, Y. Water-bath assisted convective assembly of aligned silver nanowire films for transparent electrodes. Phys. Chem. Chem. Phys. 2015, 17, 8106–8112.CrossRefGoogle Scholar
  38. [38]
    Dai, H.; Ding, R. Q.; Li, M. C.; Huang, J.; Li, Y. F.; Trevor, M. Ordering Ag nanowire arrays by spontaneous spreading of volatile droplet on solid surface. Sci. Rep. 2014, 4, 6742.CrossRefGoogle Scholar
  39. [39]
    Ko, Y. U.; Kim, N. H.; Lee, N. R.; Chang, S. T. Meniscusdragging deposition of single-walled carbon nanotubes for highly uniform, large-area, transparent conductors. Carbon 2014, 77, 964–972.CrossRefGoogle Scholar
  40. [40]
    Landau, L.; Levich, B. Dragging of a liquid by a moving plate. Acta Physicochim. URSS 1942, 17, 42–54.Google Scholar
  41. [41]
    White, D. A.; Tallmadge, J. A. Theory of drag out of liquids on flat plates. Chem. Eng. Sci. 1965, 20, 33–37.CrossRefGoogle Scholar
  42. [42]
    Wang, R. R.; Zhai, H. T.; Wang, T.; Wang, X.; Cheng, Y.; Shi, L. J.; Sun, J. Plasma-induced nanowelding of a copper nanowire network and its application in transparent electrodes and stretchable conductors. Nano Res. 2016, 9, 2138–2148.CrossRefGoogle Scholar
  43. [43]
    Lim, G.-H.; Lee, N.-E.; Lim, B. Highly sensitive, tunable, and durable gold nanosheet strain sensors for human motion detection. J. Mater. Chem. C 2016, 4, 5642–5647.CrossRefGoogle Scholar
  44. [44]
    Lee, J.; Lee, I.; Kim, T.-S.; Lee, J.-Y. Efficient welding of silver nanowire networks without post-processing. Small 2013, 9, 2887–2894.CrossRefGoogle Scholar
  45. [45]
    Sachse, C.; Weiß, N.; Gaponik, N.; Müller-Meskamp, L.; Eychmüller, A.; Leo, K. ITO-free, small-molecule organic solar cells on spray-coated copper-nanowire-based transparent electrodes. Adv. Energy Mater. 2014, 4, 1300737.CrossRefGoogle Scholar
  46. [46]
    Won, Y.; Kim, A.; Lee, D.; Yang, W.; Woo, K.; Jeong, S.; Moon, J. Annealing-free fabrication of highly oxidationresistive copper nanowire composite conductors for photovoltaics. NPG Asia Mater. 2014, 6, e105.CrossRefGoogle Scholar
  47. [47]
    Yang, H. Y.; Park, H.-W.; Kim, S. J.; Hong, J.-M.; Kim, T. W.; Kim, D. H.; Lim, J. A. Intense pulsed light induced crystallization of a liquid-crystalline polymer semiconductor for efficient production of flexible thin-film transistors. Phys. Chem. Chem. Phys. 2016, 18, 4627–4634.CrossRefGoogle Scholar
  48. [48]
    Guo, H. Z.; Lin, N.; Chen, Y. Z.; Wang, Z. W.; Xie, Q. S.; Zheng, T. C.; Gao, N.; Li, S. P.; Kang, J. Y.; Cai, D. J. et al. Copper nanowires as fully transparent conductive electrodes. Sci. Rep. 2013, 3, 2323.CrossRefGoogle Scholar
  49. [49]
    Tang, Y.; Gong, S.; Chen, Y.; Yap, L. W.; Cheng, W. L. Manufacturable conducting rubber ambers and stretchable conductors from copper nanowire aerogel monoliths. ACS Nano 2014, 8, 5707–5714.CrossRefGoogle Scholar
  50. [50]
    Rathmell, A. R.; Bergin, S. M.; Hua, Y.-L.; Li, Z.-Y.; Wiley, B. J. The growth mechanism of copper nanowires and their properties in flexible, transparent conducting films. Adv. Mater. 2010, 22, 3558–3563.CrossRefGoogle Scholar
  51. [51]
    Kim, U. J.; Lee, I. H.; Bae, J. J.; Lee, S.; Han, G. H.; Chae, S. J.; Güneş, F.; Choi, J. H.; Baik, C. W.; Kim, S. et al. Graphene/carbon nanotube hybrid-based transparent 2D optical Array. Adv. Mater. 2011, 23, 3809–3814.Google Scholar

Copyright information

© Tsinghua University Press and Springer-Verlag Berlin Heidelberg 2017

Authors and Affiliations

  • Zhenxing Yin
    • 1
  • Seung Keun Song
    • 2
  • Sanghun Cho
    • 1
  • Duck-Jae You
    • 1
  • Jeeyoung Yoo
    • 1
  • Suk Tai Chang
    • 2
  • Youn Sang Kim
    • 1
    • 3
  1. 1.Program in Nano Science and Technology, Graduate School of Convergence Science and TechnologySeoul National UniversitySeoulRepublic of Korea
  2. 2.School of Chemical Engineering and Materials ScienceChung-Ang UniversitySeoulRepublic of Korea
  3. 3.Advanced Institutes of Convergence TechnologyGyeonggi-doRepublic of Korea

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