Ion-beam-irradiated CYTOP-transferred graphene for liquid crystal cells
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The twisted nematic liquid crystal cell was developed by using a CYTOP-transferred graphene sheet as an electrode and an alignment layer. A graphene layer was synthesized by chemical vapor deposition and transferred onto a plastic substrate using a fluoropolymer known as CYTOP. As the ion-beam treatment time increased, the sheet resistance increased from 500 to 1100 Ω/sq., while the water contact angle decreased from 110.5° to 69.7°. The increased intensities of the D and G′ bands and the appearance of D + D″ and D + G′ bands in the Raman spectra indicated the formation of defects because of the ion-beam treatment. An ion-beam exposure time of 15 s was found to be the most effective for the production of CYTOP-transferred graphene and for achieving high contrast in operating cells. The ion beam detached F from the CYTOP-transferred graphene layer, and the resulting exposure of the C=C bond on the graphene surface affected the alignment of liquid crystal molecules. Based on these results, the technique described here has applications in novel, high-performance liquid crystal displays that do not require indium-tin-oxide electrodes and polyimide alignment layers. Sheets synthesized by chemical vapor deposition were transferred and simultaneously doped using fluoropolymer supporting layers.
Keywordsgraphene fluoropolymer ion-beam irradiation transparent electrode alignment layer liquid crystal displays
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- 3.P. Chaudhari, J. Lacey, J. Doyle, E. Galligan, S.-C. A. Lien, A. Callegari, G. Hougham, N. D. Lang, P. S. Andry, R. John, K.-H. Yang, M. Lu, C. Cai, J. Speidell, S. Purushothaman, J. Ritsko, M. Samant, J. Stöhr, Y. Nakagawa, Y. Katoh, Y. Saitoh, K. Sakai, H. Satoh, S. Odahara, H. Nakano, J. Nakagaki, and Y. Shiota, Nature 411, 56 (2001).CrossRefGoogle Scholar
- 16.M. J. Kiani, E. Akbari, F. Rahmanian Kooshkaki, and A. Zeinalinezhad, Electron. Mater. Lett. 12, 2193 (2016).Google Scholar