Browsing by Author "Liu, Gui-Shi"

Now showing 1 - 9 of 9

Electrically robust silver nanowire patterns transferrable onto various substrates
(2016)
Liu, Gui-Shi
;
Liu, Chuan
;
Chen, Hui-Jiuan
;
Cao, Wu
;
Qiu, Jing-Shen
We report a facile technique for patterning and transferring silver nanowires (AgNWs) onto various substrates. By employing only UV/O-3 and vapor treatment of hexamethyldisilazane (HMDS), we are able to accurately manipulate the surface energy via alternating the terminal groups of a polydimethylsiloxane (PDMS) substrate, so as to assist selective formation and exfoliation of AgNW films. A simple UV/O-3 treatment on PDMS enables uniform, well-defined, and highly conductive patterns of AgNWs after spin-coating. A vapor treatment of HMDS lowers the surface energy of the oxidized PDMS so that the patterned AgNWs embedded in an epoxy resin (EPR) are cleanly transferred from the PDMS to the target substrate. It is found that the AgNW-EPR composite on polyethylene glycol terephthalate (PET) exhibits remarkable durability under the bending test, tape test, ultrasonic treatment in water, and immersion of chemical solvents. In addition, we demonstrate that the AgNW-EPR composite work well as conductive patterns on the oxidized PDMS, polyvinyl alcohol (PVA), paper, and curved glass. The facile technique extends the applicability of AgNWs in the field of electronics, and it is potentially applicable to other nanomaterials.
Enhancement of Polar Phases in PVDF by Forming PVDF/SiC Nanowire Composite
(2016-12)
Huang, Jie-Fang
;
Han, Song-Jia
;
Chen, Hui-Jiuan
;
Liu, Gui-Shi
;
Li, Gong-Tan
Different contents of silicon carbide (SiC) nanowires were mixed with Poly(vinylidene fluoride) (PVDF) to facilitate the polar phase crystallization. It was shown that the annealing temperature and SiC content affected on the phase and crystalline structures of PVDF/SiC samples. Furthermore, the addition of SiC nanowire enhanced the transformation of non -polar a phase to polar phases and increased the relative fraction of 13 phase in PVDF. Due to the nucleating agent mechanism of SiC nanowires, the ion dipole interaction between the negatively charged surface of SiC nanowires and the positive CH2 groups in PVDF facilitated the formation of polar phases in PVDF.
Enhancement of Polar Phases in PVDF by Forming PVDF/SiC Nanowire Composite
(2016-12)
Huang, Jie-Fang
;
Han, Song-Jia
;
Chen, Hui-Jiuan
;
Liu, Gui-Shi
;
Li, Gong-Tan
Different contents of silicon carbide (SiC) nanowires were mixed with Poly(vinylidene fluoride) (PVDF) to facilitate the polar phase crystallization. It was shown that the annealing temperature and SiC content affected on the phase and crystalline structures of PVDF/SiC samples. Furthermore, the addition of SiC nanowire enhanced the transformation of non -polar a phase to polar phases and increased the relative fraction of 13 phase in PVDF. Due to the nucleating agent mechanism of SiC nanowires, the ion dipole interaction between the negatively charged surface of SiC nanowires and the positive CH2 groups in PVDF facilitated the formation of polar phases in PVDF.
Fabrication of Embedded Silver Nanowires on Arbitrary Substrates with Enhanced Stability via Chemisorbed Alkanethiolate
(2017-05-03)
Liu, Gui-Shi
;
Qiu, Jing-Shen
;
Xu, Duo-Hua
;
Zhou, Xianzhong
;
Zhong, Dingyong
We propose a versatile yet practical transferring technique to fabricate a high performance and extremely stable silver nanowire (AgNW) transparent electrode on arbitrary substrates. Hydroxylated polyethylene glycol) terephthalate (PET) or poly(dimethylsiloxane) (PDMS) deposited with AgNWs was selectively decorated to lower its polar surface energy, so that the AgNWs were easily and efficiently transferred into an epoxy resin (EPR) as a freestanding film (AgNWs EPR) or onto various substrates. The AgNWs EPR capped with alkanethiolate monolayers exhibits high conductivity, low roughness, ultraflexibility, and strong corrosion resistance. Using the transferring process, AgNWs EPR was successfully constructed on rough, adhesive, flimsy, or complex curved substrates, including PET, thin optically clear adhesive, papers, a beaker, convex spherical PDMS, and leaves. A flexible touch panel enabling multitouch and a curved transparent heater on a beaker were first fabricated by using the composite film. These demonstrations suggest that the proposed technique for AgNWs is a promising strategy toward the next generation of flexible/portable/wearable electronics.
Hybrid Effect of Crossed Alignment and Multi-Stacking Structure on the Percolation Behavior of Silver Nanowire Networks
(2015-07-01)
Yang, Bo-Ru
;
Liu, Gui-Shi
;
Han, Song-Jia
;
Cao, Wu
;
Chen, Hui-Jiuan
Owing to the superiority of being flexible, highly conductive, and extremely transparent, silver nanowire (AgNW) has been regarded as a possible candidate to replace indium-tin-oxide (ITO) for flexible transparent conductive films (TCFs), flexible electronics, and flexible display applications. To make TCFs with lower sheet resistance (R-s), but without sacrificing the optical transmittance, the deployment of AgNWs is very critical. A crossed-alignment method along with multi-stacking structure was proposed to lower the percolative threshold, which thus can decrease the R-s by a factor of more than two, in the premise of not affecting the optical transmittance.
Microchannel Wetting for Controllable Patterning and Alignment of Silver Nanowire with High Resolution
(2015-09-30)
Yang, Bo-Ru
;
Cao, Wu
;
Liu, Gui-Shi
;
Chen, Hui-Jiuan
;
Noh, Yong-Young
Patterning and alignment of conductive nanowires are essential for good electrical isolation and high conductivity in various applications. Herein a facile bottom-up, additive technique is developed to pattern and align silver nanowires (AgNWs) by manipulating wetting of dispersions in microchannels. By forming hydrophobic/hydrophilic micropatterns down to 8 mu m with fiuoropolymer (Cytop) and SiO2, the aqueous AgNW dispersions with the optimized surface tension and viscosity self-assemble into microdroplets and then dry to form anisotropic AgNW networks. The alignment degree characterized by the full width at half-maximum (FWHM) can be well-controlled from 39.8 degrees to 84.1 degrees by changing the width of microchannels. A mechanism is proposed and validated by statistical analysis on AgNW alignment, and a static model is proposed to guide the patterning of general NWs. The alignment reduced well the electrical resistivity of AgNW networks by a factor of 5 because of the formation of efficient percolation path for carrier conduction.
Selective Deposition of Silver Nanowires and Its Application for Wearable Pressure Sensor
(2016-01-01)
Liu, Gui-Shi
;
Qiu, Jing-Sen
;
Yang, Bo-Ru
;
Shieh, Han-Ping D.
;
光電工程學系
Wearable, highly sensitive, and low-cost pressure sensors are desirable in the field of electronic skin. Here we report a solution-processed fabrication strategy to construct a highly sensitive, flexible pressure sensor by laminating silver nanowire (AgNW) patterns/Polydimethylsiloxane (PDMS) layer and poly(3, 4-ethylenedioxythiophene): poly(styrenesulfonate) (PEDOT:PSS)/PDMS layer with micro-structure. The AgNWs with interdigitated pattern, as an electrode, was fabricated by a wetting/dewetting process. The micro-structure of the PEDOT: PSS/PDMS layer was replicated from a sandpaper. The sensors are able to detect the pressure as low as 100 Pa with large pressure region (up to 140 kPa) and fast response time (<40 ms).
Stability Enhancement of Silver Nanowire Patterns by Transferring Process
(2016)
Liu, Gui-Shi
;
Liu, Chuan
;
Chen, Jiuan-Hui
;
Shieh, Han-Ping D.
;
Yang, Bo-Ru
Silver nanowires (AgNWs) need to be patterned for using as transparent conductive electrodes (TCEs) in most electronic devices. Herein we propose a versatile technique which can fabricate AgNW patterns with enhanced adhesion to the substrate of polyethylene glycol terephthalate (PET). By using spin-coating, AgNWs were self-assembled into patterns on the surface of polydimethylsiloxane (PDMS) which had been patterned with high contrast of wettability by UV/O-3 exposure. To enhance the adhesion of AgNWs to substrate, the patterned AgNWs were embedded into epoxy resin (EPR) by a facile transferring process. The key to this process is the anti-adhesive groups (CH3) grafted on the oxidized PDMS to assist a clean exfoliation. The AgNW-EPR composite electrode exhibits excellent stability under adhesive tape test and long-term storage.
Transfer printing for fabrication of flexible RGB color e-paper
(2017-06-01)
Wang, Li
;
Liu, Gui-Shi
;
Wang, Yu-Cheng
;
Su, Jing
;
Wang, Xi-Du
Electrophoretic display (EPD) has been a prevailing paper-like display technology for years, owing to its advantages of flexibility, low-power consumption, and good sunlight readability. However, it is regrettable that the black/white EPD still dominates the majority of the market while a commercially sold full-color EPD is still unavailable. In this paper, we proposed a facile yet feasible method to fabricate a color EPD by a tape-assisted transfer method, which is the first demonstration using transfer method to achieve color micro-encapsulated EPD.