The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform

Huai Yang - One of the best experts on this subject based on the ideXlab platform.

Gregory P. Crawford - One of the best experts on this subject based on the ideXlab platform.

Jinyeong Park - One of the best experts on this subject based on the ideXlab platform.

  • highly stretchable polymer dispersed Liquid Crystal based smart windows with transparent and stretchable hybrid electrodes
    RSC Advances, 2018
    Co-Authors: Jinyeong Park
    Abstract:

    We report on highly stretchable polymer dispersed Liquid Crystal (PDLC)-based smart windows using Ag nanowires (NWs) and conductive PEDOT:PSS hybrid electrodes. By bar coating a Ag NW and PEDOT:PSS mixed ink on a transparent and stretchable polyurethane (PU) substrate, we fabricated highly transparent and stretchable hybrid electrodes with a sheet resistance of 40 ohm per square, an optical transmittance of 82%, and a stretchability of 30% to replace conventional brittle ITO electrode. Bending and stretching tests demonstrated that the mechanical properties of the Ag NW and PEDOT:PSS hybrid electrode were better than those of the ITO/PU sample. The Ag NW/PEDOT:PSS hybrid film was employed as a transparent and stretchable electrode (TSE) in PDLC-based stretchable smart windows, an application that is impossible for brittle ITO-based smart windows. The stretchable PDLC-based smart windows exhibited an on-state transmittance of 56% at an applied voltage of 80 V and an off-state transmittance of 2% at 0 voltage. Unlike an ITO-based PDLC smart window, which is easily broken by stretching, the Ag NW/PEDOT:PSS hybrid electrode-based PDLC smart window was stretched up to 30%. Successful operation of the stretchable PDLC-based smart window indicates that Ag NW/PEDOT:PSS hybrid films are promising TSEs for cost-effective, large area, and stretchable smart windows.

  • Liquid Crystal based flexible smart windows on roll to roll slot die coated ag nanowire network films
    Journal of Alloys and Compounds, 2018
    Co-Authors: Dongju Kim, Jinyeong Park, Do Yun Hwang, Hanki Kim
    Abstract:

    Abstract We developed polymer dispersed Liquid Crystal (PDLC)-based large-area flexible smart windows using continuous roll-to-roll (RTR) slot die–coated Ag nanowire (NW) percolating network electrodes. By simply printing Ag NW ink on flexible poly(ethylene terephthalate) (PET) substrates with 400 mm width, we fabricated cost-effective, transparent, and flexible Ag NW electrodes with a low sheet resistance of 50 Ohm/square and high transmittance of 88% for high-performance and large-area flexible PDLCs. Although the Ag NW electrode exhibited similar electrical and optical properties to typical indium tin oxide (ITO) electrodes, the Ag NW electrode had superior flexibility to the brittle ITO, which is important for flexible PDLCs. The PDLC window fabricated with the Ag NW electrode exhibited good transparency switching performance and outstanding flexibility. By producing a PDLC window with a width of 400 mm and length of 2 m, we demonstrated the feasibility of large-area flexible PLDCs based on continuous RTR-coated Ag NW electrodes for smart windows.

Li Xuan - One of the best experts on this subject based on the ideXlab platform.

  • organic solid state tri wavelength lasing from holographic polymer dispersed Liquid Crystal and a distributed feedback laser with a doped laser dye and a semiconducting polymer film
    Materials, 2017
    Co-Authors: M Liu, Yonggang Liu, Zenghui Peng, Shaoxin Wang, Qidong Wang, Zhaoliang Cao, Li Xuan
    Abstract:

    Organic solid-state tri-wavelength lasing was demonstrated from dye-doped holographic Polymer-Dispersed Liquid Crystal (HPDLC) distributed feedback (DFB) laser with semiconducting polymer poly[-methoxy-5-(2′-ethyl-hexyloxy)-1,4-phenylene-vinylene] (MEH-PPV) and laser dye [4-(dicyanomethylene)-2-methyl-6-(p-dimethylaminostyryl)-4H-pyran] (DCM) by a one-step holography technique, which centered at 605.5 nm, 611.9 nm, and 671.1 nm. The temperature-dependence tuning range for the tri-wavelength dye-doped HPDLC DFB laser was as high as 8 nm. The lasing emission from the 9th order HPDLC DFB laser with MEH-PPV as active medium was also investigated, which showed excellent s-polarization characterization. The diffraction order is 9th and 8th for the dual-wavelength lasing with DCM as the active medium. The results of this work provide a method for constructing the compact and cost-effective all solid-state smart laser systems, which may find application in scientific and applied research where multi-wavelength radiation is required.

  • effects of monomer functionality on performances of scaffolding morphologic transmission gratings recorded in polymer dispersed Liquid Crystals
    Journal of Physics D, 2015
    Co-Authors: Wenbin Huang, Donglin Pu, Su Shen, Li Xuan, Linsen Chen
    Abstract:

    The effects of monomer functionality on performances of holographic polymer dispersed Liquid Crystal (HPDLC) transmission gratings are systematically investigated. Acrylate monomers with an average functionality ranging from 2.0 to 5.0 are used to prepare these samples. We find scaffolding morphologic transmission gratings (characterized by a high phase separation degree, a well alignment of LCs and low scattering loss) can be obtained irrespective of the monomer functionality, although the exact optimal curing intensity varies. The temporal evolution of the grating formation is studied and the onset time of the LC phase separation decreases significantly with the increase in average monomer functionality. It is also shown that the gratings prepared from low average functionality monomers require a comparatively low switch-off electric field (~8 V μm−1) whilst suffering from mechanical fragility and long-term instability. Our results not only provide a complete understanding of scaffolding morphologic gratings in terms of the material composition effect, but also provide insight into the formation mechanisms of non-droplet morphologic HPDLC gratings.

  • Enhancement of pump efficiency for an organic distributed feedback laser based on a holographic polymer dispersed Liquid Crystal as an external light feedback layer
    Journal of Materials Chemistry C, 2015
    Co-Authors: Lijuan Liu, Minghuan Liu, Lifa Hu, Guiyang Zhang, Yonggang Liu, Li Xuan, Ji Ma
    Abstract:

    We report a low threshold, high energy conversion organic distributed feedback (DFB) laser based on a holographic polymer dispersed Liquid Crystal (HPDLC) grating as an external light feedback layer, specifically, by adopting an acrylate-based monomer with low functionality and a rubbed polyimide (PI) alignment layer. In such configuration, the phase separated LCs were aligned along the preferred direction, which gave an increased refractive index difference between the LC and the polymer, so it can provide better light feedback in the HPDLC layer. The pump efficiency for the laser, such as lasing output threshold and conversion efficiency, can be enhanced. The light loss, diffraction efficiency and driving voltage were also investigated for the HPDLC structures to identify the effects of the rubbing layer and monomer functionality.

  • organic dual wavelength distributed feedback laser empowered by dye doped holography
    Journal of Materials Chemistry, 2012
    Co-Authors: Zhihui Diao, Wenbin Huang, Li Xuan, Shupeng Deng, Yonggang Liu
    Abstract:

    An organic dual-wavelength distributed feedback (DFB) laser empowered by a dye-doped holographic polymer dispersed Liquid Crystal (HPDLC) grating is reported for the first time. The dual-wavelength laser operates at 586.6 nm and 670.2 nm simultaneously in one laser beam via the seventh and eighth Bragg orders of a one dimensional (1D) HPDLC grating with a special period. We theoretically and experimentally demonstrate the mechanism of our dual-wavelength DFB laser and investigate the threshold and spectral properties of the output laser. Our organic dual-wavelength DFB laser shows the advantages of simple configuration, one-step fabrication, cost-effectiveness and the potential application to be integrated in all optical networks.

  • theory and characteristics of holographic polymer dispersed Liquid Crystal transmission grating with scaffolding morphology
    Applied Optics, 2012
    Co-Authors: Wenbin Huang, Yonggang Liu, Zhihui Diao, Chengliang Yang, Lishuang Yao, Li Xuan
    Abstract:

    We have performed a detailed characterization of the optical properties of a holographic polymer dispersed Liquid Crystal (LC) transmission grating with polymer scaffolding morphology, which was fabricated with conventional high-functionality acrylate monomer under low curing intensity. Temporal evolution of the grating formation was investigated, and the amount of phase-separated LC was determined by birefringence investigation. A grating model combined with anisotropic coupled-wave theory yielded good agreement with experimental data without any fitting parameter. The results in this study demonstrate the non droplet scaffolding morphology grating is characterized by a high degree of phase separation (70%), high anisotropy, low scattering loss (<6%), and high diffraction efficiency (95%).

Henning Sirringhaus - One of the best experts on this subject based on the ideXlab platform.

  • inkjet printing of polymer thin film transistor circuits
    Mrs Bulletin, 2003
    Co-Authors: S E Burns, Paul A Cain, J Mills, Jizheng Wang, Henning Sirringhaus
    Abstract:

    We present a process for manufacturing printable thin-film transistors (TFTs) that is based on solution processing and direct inkjet printing of polymer semiconductors, dielectrics, and conductors, as well as inorganic nanoparticle conductors. We show that the high device yield, uniformity, and resolution required for thin-film electronic applications can be achieved by using a substrate that contains a surface energy pattern to control the flow and spreading of inkjet droplets. This technique overcomes many of the limitations of current inkjet printing technology related to its limited droplet placement accuracy. We demonstrate the potential of this printing-based TFT manufacturing process with the fabrication of 50 dpi active-matrix, polymer dispersed Liquid-Crystal and Gyricon Smartpaper electronic paper displays.