Issue

Vol. 17 (2025)

Ultra-Transparent and Multifunctional IZVO Mesh Electrodes for Next-Generation Flexible Optoelectronics

https://doi.org/10.1007/s40820-024-01525-y
Kiran A. Nirmal
School of Electrical Engineering, Korea University, Anam‑ro 145, Seongbuk‑gu, Seoul, Republic of Korea
Tukaram D. Dongale
Computational Electronics and Nanoscience Research Laboratory, School of Nanoscience and Biotechnology, Shivaji University, Kolhapur 416004, India
Atul C. Khot
School of Electrical Engineering, Korea University, Anam‑ro 145, Seongbuk‑gu, Seoul, Republic of Korea
Chenjie Yao
School of Electrical Engineering, Korea University, Anam‑ro 145, Seongbuk‑gu, Seoul, Republic of Korea
Nahyun Kim
School of Electrical Engineering, Korea University, Anam‑ro 145, Seongbuk‑gu, Seoul, Republic of Korea
Tae Geun Kim
School of Electrical Engineering, Korea University, Anam‑ro 145, Seongbuk‑gu, Seoul, Republic of Korea

Corresponding Author: Tae Geun Kim

tgkim1@korea.ac.kr

Nano-Micro Letters, Vol. 17 (2025), Article Number: 12

Abstract

Mechanically durable transparent electrodes are essential for achieving long-term stability in flexible optoelectronic devices. Furthermore, they are crucial for applications in the fields of energy, display, healthcare, and soft robotics. Conducting meshes represent a promising alternative to traditional, brittle, metal oxide conductors due to their high electrical conductivity, optical transparency, and enhanced mechanical flexibility. In this paper, we present a simple method for fabricating an ultra-transparent conducting metal oxide mesh electrode using self-cracking-assisted templates. Using this method, we produced an electrode with ultra-transparency (97.39%), high conductance (Rs = 21.24 Ω sq−1), elevated work function (5.16 eV), and good mechanical stability. We also evaluated the effectiveness of the fabricated electrodes by integrating them into organic photovoltaics, organic light-emitting diodes, and flexible transparent memristor devices for neuromorphic computing, resulting in exceptional device performance. In addition, the unique porous structure of the vanadium-doped indium zinc oxide mesh electrodes provided excellent flexibility, rendering them a promising option for application in flexible optoelectronics.


Highlights:
1 Ultra-transparent vanadium-doped indium zinc oxide mesh (mIZVO) electrodes are fabricated using a self-cracking template.
2 Fabricated electrodes are employed to realize flexible organic solar cell (OSC), organic light-emitting diode (OLED), and memristor devices. OSC exhibits 14.38% power conversion efficiency and OLED achieves 18.06% external quantum efficiency with mIZVO electrode.
3 Flexible-transparent memristor based on mIZVO mimics various synaptic functions.

Keywords

Self-cracking template Vanadium-doped indium zinc oxide mesh Organic solar cells Organic light-emitting diodes Flexible transparent memory
Nirmal, Kiran A., Tukaram D. Dongale, Atul C. Khot, Chenjie Yao, Nahyun Kim, and Tae Geun Kim. 2024. “Ultra-Transparent and Multifunctional IZVO Mesh Electrodes for Next-Generation Flexible Optoelectronics”. Nano-Micro Letters 17 (September):12. https://doi.org/10.1007/s40820-024-01525-y.
Download Citation
Endnote/Zotero/Mendeley (RIS)
BibTeX
References
  1. J. Wang, W. Yang, Z. Liu, Y. Su, K. Li et al., Ultra-fine self-powered interactive fiber electronics for smart clothing. Nano Energy 107, 108171 (2023). https://doi.org/10.1016/j.nanoen.2023.108171
  2. H.S. Jo, C.-W. Park, S. An, A. Aldalbahi, M. El-Newehy et al., Wearable multifunctional soft sensor and contactless 3D scanner using supersonically sprayed silver nanowires, carbon nanotubes, zinc oxide, and PEDOT: PSS. npg Asia Mater. 14, 23 (2022). https://doi.org/10.1038/s41427-022-00370-y
  3. R. Yoshikawa, M. Tenjimbayashi, T. Matsubayashi, K. Manabe, L. Magagnin et al., Designing a flexible and transparent ultrarapid electrothermogenic film based on thermal loss suppression effect: a self-fused Cu/Ni composite junctionless nanonetwork for effective deicing heater. ACS Appl. Nano Mater. 1, 860–868 (2018). https://doi.org/10.1021/acsanm.7b00268
  4. S. Kumar, Y. Seo, Flexible transparent conductive electrodes: unveiling growth mechanisms, material dimensions, fabrication methods, and design strategies. Small Methods 8, e2300908 (2024). https://doi.org/10.1002/smtd.202300908
  5. S. Lan, S. Yoon, H.-J. Seok, H.U. Ha, D.-W. Kang et al., Low-temperature deposited highly flexible In–Zn–V–O transparent conductive electrode for perovskite solar cells. ACS Appl. Energy Mater. 5, 234–248 (2022). https://doi.org/10.1021/acsaem.1c02771
  6. P. Gutruf, C.M. Shah, S. Walia, H. Nili, A.S. Zoolfakar et al., Transparent functional oxide stretchable electronics: micro-tectonics enabled high strain electrodes. npg Asia Mater. 5, e62 (2013). https://doi.org/10.1038/am.2013.41
  7. W. Brütting, J. Frischeisen, T.D. Schmidt, B.J. Scholz, C. Mayr, Device efficiency of organic light-emitting diodes: Progress by improved light outcoupling. Phys. Status Solidi A 210, 44–65 (2013). https://doi.org/10.1002/pssa.201228320
  8. Y. Yang, Q. Huang, A. Metz, J. Ni, S. Jin et al., High-performance organic light-emitting diodes using ITO anodes grown on plastic by room- temperature ion-assisted deposition. Adv. Mater. 16, 321–324 (2004). https://doi.org/10.1002/adma.200305727
  9. M. Park, H.J. Kim, I. Jeong, J. Lee, H. Lee et al., Mechanically recoverable and highly efficient perovskite solar cells: investigation of intrinsic flexibility of organic-inorganic perovskite. Adv. Energy Mater. 5, 1501406 (2015). https://doi.org/10.1002/aenm.201501406
  10. C.-K. Cho, W.-J. Hwang, K. Eun, S.-H. Choa, S.-I. Na et al., Mechanical flexibility of transparent PEDOT: PSS electrodes prepared by gravure printing for flexible organic solar cells. Sol. Energy Mater. Sol. Cells 95, 3269–3275 (2011). https://doi.org/10.1016/j.solmat.2011.07.009
  11. A. Khan, S. Lee, T. Jang, Z. Xiong, C. Zhang et al., High-performance flexible transparent electrode with an embedded metal mesh fabricated by cost-effective solution process. Small 12, 3021–3030 (2016). https://doi.org/10.1002/smll.201600309
  12. H. Li, D. Zi, X. Zhu, H. Zhang, Y. Tai et al., Electric field driven printing of repeatable random metal meshes for flexible transparent electrodes. Opt. Laser Technol. 157, 108730 (2023). https://doi.org/10.1016/j.optlastec.2022.108730
  13. Z. Li, H. Li, X. Zhu, Z. Peng, G. Zhang et al., Directly printed embedded metal mesh for flexible transparent electrode via liquid substrate electric-field-driven jet. Adv. Sci. 9, e2105331 (2022). https://doi.org/10.1002/advs.202105331
  14. A. Manikandan, L. Lee, Y.-C. Wang, C.-W. Chen, Y.-Z. Chen et al., Graphene-coated copper nanowire networks as a highly stable transparent electrode in harsh environments toward efficient electrocatalytic hydrogen evolution reactions. J. Mater. Chem. A 5, 13320–13328 (2017). https://doi.org/10.1039/C7TA01767G
  15. J. Yang, L. Chang, H. Zhao, X. Zhang, Z. Cao et al., Multilayer ordered silver nanowire network films by self-driven climbing for large-area flexible optoelectronic devices. InfoMat 6, e12529 (2024). https://doi.org/10.1002/inf2.12529
  16. H. Kang, S. Jung, S. Jeong, G. Kim, K. Lee, Polymer-metal hybrid transparent electrodes for flexible electronics. Nat. Commun. 6, 6503 (2015). https://doi.org/10.1038/ncomms7503
  17. J. Yoon, H. Sung, G. Lee, W. Cho, N. Ahn et al., Superflexible, high-efficiency perovskite solar cells utilizing graphene electrodes: towards future foldable power sources. Energy Environ. Sci. 10, 337–345 (2017). https://doi.org/10.1039/c6ee02650h
  18. B. Rezaei, F. Afshar-Taromi, Z. Ahmadi, S. Amiri-Rigi, N. Yousefi, High conductive ITO-free flexible electrode based on Gr-grafted-CNT/Au NPs for optoelectronic applications. Opt. Mater. 89, 441–451 (2019). https://doi.org/10.1016/j.optmat.2019.01.053
  19. K.A. Nirmal, W. Ren, A.C. Khot, D.Y. Kang, T.D. Dongale et al., Flexible memristive organic solar cell using multilayer 2D titanium carbide MXene electrodes. Adv. Sci. 10, e2300433 (2023). https://doi.org/10.1002/advs.202300433
  20. L. Qin, J. Jiang, Q. Tao, C. Wang, I. Persson et al., A flexible semitransparent photovoltaic supercapacitor based on water-processed MXene electrodes. J. Mater. Chem. A 8, 5467–5475 (2020). https://doi.org/10.1039/D0TA00687D
  21. J.J. Kim, K. Shuji, J. Zheng, X. He, A. Sajjad et al., Tri-system integration in metal-oxide nanocomposites via in situ solution-processed method for ultrathin flexible transparent electrodes. Nat. Commun. 15, 2070 (2024). https://doi.org/10.1038/s41467-024-46243-6
  22. S. Parthiban, J.-Y. Kwon, Amorphous boron–indium–zinc-oxide active channel layers for thin-film transistor fabrication. J. Mater. Chem. C 3, 1661–1665 (2015). https://doi.org/10.1039/C4TC01831A
  23. X. Zhang, B. Wang, W. Huang, Y. Chen, G. Wang et al., Synergistic boron doping of semiconductor and dielectric layers for high-performance metal oxide transistors: interplay of experiment and theory. J. Am. Chem. Soc. 140, 12501–12510 (2018). https://doi.org/10.1021/jacs.8b06395
  24. E.-H. Ko, H.-K. Kim, Highly transparent vanadium oxide-graded indium zinc oxide electrodes for flexible organic solar cells. Thin Solid Films 601, 2–6 (2016). https://doi.org/10.1016/j.tsf.2015.11.067
  25. H.D. Um, D. Choi, A. Choi, J.H. Seo, K. Seo, Embedded metal electrode for organic-inorganic hybrid nanowire solar cells. ACS Nano 11, 6218–6224 (2017). https://doi.org/10.1021/acsnano.7b02322
  26. J. Yang, C. Bao, K. Zhu, T. Yu, Q. Xu, High-performance transparent conducting metal network electrodes for perovksite photodetectors. ACS Appl. Mater. Interfaces 10, 1996–2003 (2018). https://doi.org/10.1021/acsami.7b15205
  27. N. Kim, J. Hwang, H.J. Lee, N.Y. Kwon, J.Y. Park et al., Work-function-tunable metal-oxide mesh electrode and novel soluble bipolar host for high-performance solution-processed flexible TADF-OLED. Nano Energy 105, 108028 (2023). https://doi.org/10.1016/j.nanoen.2022.108028
  28. T. Qiu, B. Luo, E.M. Akinoglu, J.-H. Yun, I.R. Gentle et al., Trilayer nanomesh films with tunable wettability as highly transparent, flexible, and recyclable electrodes. Adv. Funct. Mater. 30, 2002556 (2020). https://doi.org/10.1002/adfm.202002556
  29. Y. Zhang, Z. Lu, X. Zhou, J. Xiong, Metallic meshes for advanced flexible optoelectronic devices. Mater. Today 73, 179–207 (2024). https://doi.org/10.1016/j.mattod.2024.01.006
  30. J. Gao, Z. Xian, G. Zhou, J.-M. Liu, K. Kempa, Nature-inspired metallic networks for transparent electrodes. Adv. Funct. Mater. 28, 1705023 (2018). https://doi.org/10.1002/adfm.201705023
  31. Y.G. Kim, Y.J. Tak, S.P. Park, H.J. Kim, H.J. Kim, Structural engineering of metal-mesh structure applicable for transparent electrodes fabricated by self-formable cracked template. Nanomaterials (Basel) 7, 214 (2017). https://doi.org/10.3390/nano7080214
  32. P. Liu, B. Huang, L. Peng, L. Liu, Q. Gao et al., A crack templated copper network film as a transparent conductive film and its application in organic light-emitting diode. Sci. Rep. 12, 20494 (2022). https://doi.org/10.1038/s41598-022-24672-x
  33. A.S. Voronin, Y.V. Fadeev, I.V. Govorun, I.V. Podshivalov, M.M. Simunin et al., Cu–Ag and Ni–Ag meshes based on cracked template as efficient transparent electromagnetic shielding coating with excellent mechanical performance. J. Mater. Sci. 56, 14741–14762 (2021). https://doi.org/10.1007/s10853-021-06206-4
  34. M. Cui, X. Zhang, Q. Rong, L. Nian, L. Shui et al., High conductivity and transparency metal network fabricated by acrylic colloidal self-cracking template for flexible thermochromic device. Org. Electron. 83, 105763 (2020). https://doi.org/10.1016/j.orgel.2020.105763
  35. B. Han, Y. Huang, R. Li, Q. Peng, J. Luo et al., Bio-inspired networks for optoelectronic applications. Nat. Commun. 5, 5674 (2014). https://doi.org/10.1038/ncomms6674
  36. C.F. Guo, T. Sun, Q. Liu, Z. Suo, Z. Ren, Highly stretchable and transparent nanomesh electrodes made by grain boundary lithography. Nat. Commun. 5, 3121 (2014). https://doi.org/10.1038/ncomms4121
  37. R. Seghir, S. Arscott, Controlled mud-crack patterning and self-organized cracking of polydimethylsiloxane elastomer surfaces. Sci. Rep. 5, 14787 (2015). https://doi.org/10.1038/srep14787
  38. M. Zarei, M. Li, E.E. Medvedeva, S. Sharma, J. Kim et al., Flexible embedded metal meshes by sputter-free crack lithography for transparent electrodes and electromagnetic interference shielding. ACS Appl. Mater. Interfaces 16, 6382–6393 (2024). https://doi.org/10.1021/acsami.3c16405
  39. Q. Peng, S. Li, B. Han, Q. Rong, X. Lu et al., Colossal figure of merit in transparent-conducting metallic ribbon networks. Adv. Mater. Technol. 1, 1600095 (2016). https://doi.org/10.1002/admt.201600095
  40. A.S. Voronin, Y.V. Fadeev, M.O. Makeev, P.A. Mikhalev, A.S. Osipkov et al., Low cost embedded copper mesh based on cracked template for highly durability transparent EMI shielding films. Materials (Basel) 15, 1449 (2022). https://doi.org/10.3390/ma15041449
  41. K. Ding, J. Shi, S. Chen, Review on stress evolution and crack propagation mechanism of double-crack specimens. Mech. Adv. Mater. Struct. (2023). https://doi.org/10.1080/15376494.2023.2253254
  42. M. Chiang, S.-H. Chang, C.-Y. Chen, F.-W. Yuan, H. Tuan, Quaternary CuIn(S1−xSex)2 nanocrystals: facile heating-up synthesis, band gap tuning, and gram-scale production. J. Phys. Chem. C 115, 1592–1599 (2011). https://doi.org/10.1021/JP1090735
  43. M. Gliboff, L. Sang, K.M. Knesting, M.C. Schalnat, A. Mudalige et al., Orientation of phenylphosphonic acid self-assembled monolayers on a transparent conductive oxide: a combined NEXAFS, PM-IRRAS, and DFT study. Langmuir 29, 2166–2174 (2013). https://doi.org/10.1021/la304594t
  44. A. Chen, K. Zhu, H. Zhong, Q. Shao, G. Ge, A new investigation of oxygen flow influence on ITO thin films by magnetron sputtering. Sol. Energy Mater. Sol. Cells 120, 157–162 (2014). https://doi.org/10.1016/j.solmat.2013.08.036
  45. G. Haacke, New figure of merit for transparent conductors. J. Appl. Phys. 47, 4086–4089 (1976). https://doi.org/10.1063/1.323240
  46. D.Y. Kang, B.H. Kim, T.H. Lee, J.W. Shim, S. Kim et al., Dopant-tunable ultrathin transparent conductive oxides for efficient energy conversion devices. Nano-Micro Lett. 13, 211 (2021). https://doi.org/10.1007/s40820-021-00735-y
  47. P. Dalle Feste, M. Crisci, F. Barbon, F. Tajoli, M. Salerno et al., Work function tuning in hydrothermally synthesized vanadium-doped MoO3 and Co3O4 mesostructures for energy conversion devices. Appl. Sci. 11, 2016 (2021). https://doi.org/10.3390/app11052016
  48. C. Zhang, A. Song, Q. Huang, Y. Cao, Z. Zhong et al., All-polymer solar cells and photodetectors with improved stability enabled by terpolymers containing antioxidant side chains. Nano-Micro Lett. 15, 140 (2023). https://doi.org/10.1007/s40820-023-01114-5
  49. H.B. Lee, W.-Y. Jin, M.M. Ovhal, N. Kumar, J.-W. Kang, Flexible transparent conducting electrodes based on metal meshes for organic optoelectronic device applications: a review. J. Mater. Chem. C 7, 1087–1110 (2019). https://doi.org/10.1039/C8TC04423F
  50. C.F. Guo, Z. Ren, Flexible transparent conductors based on metal nanowire networks. Mater. Today 18, 143–154 (2015). https://doi.org/10.1016/j.mattod.2014.08.018
  51. S. Liu, C. Zang, J. Zhang, S. Tian, Y. Wu et al., Air-stable ultrabright inverted organic light-emitting devices with metal ion-chelated polymer injection layer. Nano-Micro Lett. 14, 14 (2021). https://doi.org/10.1007/s40820-021-00745-w
  52. I.G. Jang, V. Murugadoss, T.H. Park, K.R. Son, H.J. Lee et al., Cavity-suppressing electrode integrated with multi-quantum well emitter: a universal approach toward high-performance blue TADF top emission OLED. Nano-Micro Lett. 14, 60 (2022). https://doi.org/10.1007/s40820-022-00802-y
  53. B.R. Lee, J.H. Park, T.H. Lee, T.G. Kim, Highly flexible and transparent memristive devices using cross-stacked oxide/metal/oxide electrode layers. ACS Appl. Mater. Interfaces 11, 5215–5222 (2019). https://doi.org/10.1021/acsami.8b17700
  54. J. Zhou, W. Li, Y. Chen, Y.-H. Lin, M. Yi et al., A monochloro copper phthalocyanine memristor with high-temperature resilience for electronic synapse applications. Adv. Mater. 33, e2006201 (2021). https://doi.org/10.1002/adma.202006201
  55. Y. Wei, Y. Liu, Q. Lin, T. Liu, S. Wang et al., Organic optoelectronic synapses for sound perception. Nano-Micro Lett. 15, 133 (2023). https://doi.org/10.1007/s40820-023-01116-3
  56. R. Llinás, I.Z. Steinberg, K. Walton, Relationship between presynaptic calcium current and postsynaptic potential in squid giant synapse. Biophys. J. 33, 323–351 (1981). https://doi.org/10.1016/S0006-3495(81)84899-0
  57. K.A. Nirmal, G.S. Nhivekar, A.C. Khot, T.D. Dongale, T.G. Kim, Unraveling the effect of the water content in the electrolyte on the resistive switching properties of self-assembled one-dimensional anodized TiO2 nanotubes. J. Phys. Chem. Lett. 13, 7870–7880 (2022). https://doi.org/10.1021/acs.jpclett.2c01075
  58. A.C. Khot, T.D. Dongale, K.A. Nirmal, J.H. Sung, H.J. Lee et al., Amorphous boron nitride memristive device for high-density memory and neuromorphic computing applications. ACS Appl. Mater. Interfaces 14, 10546–10557 (2022). https://doi.org/10.1021/acsami.1c23268
  59. S. Chen, T. Zhang, S. Tappertzhofen, Y. Yang, I. Valov, Electrochemical-memristor-based artificial neurons and synapses-fundamentals, applications, and challenges. Adv. Mater. 35, e2301924 (2023). https://doi.org/10.1002/adma.202301924
Read More
Author biographies are not available.
Statistic
Read Counter : 1557 Download : 1138

Most read articles by the same author(s)