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


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).

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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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Correspondence to Suk Tai Chang or Youn Sang Kim.

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Yin, Z., Song, S.K., Cho, S. et al. Curved copper nanowires-based robust flexible transparent electrodes via all-solution approach. Nano Res. 10, 3077–3091 (2017).

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