Optically Transparent Multiscale Composite Films for Flexible and Wearable Electronics

2020 ◽  
Vol 32 (35) ◽  
pp. 1907143 ◽  
Author(s):  
Young‐Woo Lim ◽  
Jungho Jin ◽  
Byeong‐Soo Bae
Keyword(s):  
Composite Films ◽  
Wearable Electronics ◽  
Multiscale Composite ◽  
Optically Transparent

scholarly journals Preparation and Characterization of Transparent Polyimide Nanocomposite Films with Potential Applications as Spacecraft Antenna Substrates with Low Dielectric Features and Good Sustainability in Atomic-Oxygen Environments

Nanomaterials ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1886
Author(s):  
Yan Zhang ◽  
Bo-han Wu ◽  
Han-li Wang ◽  
Hao Wu ◽  
Yuan-cheng An ◽  
...  
Keyword(s):  
Atomic Oxygen ◽  
Composite Films ◽  
Dissipation Factor ◽  
Low Earth Orbit ◽  
Nanocomposite Films ◽  
Dielectric Parameters ◽  
Low Dielectric ◽  
Aerospace Applications ◽  
Optically Transparent ◽  
Order Of Magnitude

Optically transparent polyimide (PI) films with good dielectric properties and long-term sustainability in atomic-oxygen (AO) environments have been highly desired as antenna substrates in low earth orbit (LEO) aerospace applications. However, PI substrates with low dielectric constant (low-Dk), low dielectric dissipation factor (low-Df) and high AO resistance have rarely been reported due to the difficulties in achieving both high AO survivability and good dielectric parameters simultaneously. In the present work, an intrinsically low-Dk and low-Df optically transparent PI film matrix, poly[4,4′-(hexafluoroisopropylidene)diphthalic anhydride-co-2,2-bis(4-(4-aminophenoxy)phenyl)hexafluoropropane] (6FPI) was combined with a nanocage trisilanolphenyl polyhedral oligomeric silsesquioxane (TSP-POSS) additive in order to afford novel organic–inorganic nanocomposite films with enhanced AO-resistant properties and reduced dielectric parameters. The derived 6FPI/POSS films exhibited the Dk and Df values as low as 2.52 and 0.006 at the frequency of 1 MHz, respectively. Meanwhile, the composite films showed good AO resistance with the erosion yield as low as 4.0 × 10−25 cm3/atom at the exposure flux of 4.02 × 1020 atom/cm2, which decreased by nearly one order of magnitude compared with the value of 3.0 × 10−24 cm3/atom of the standard PI-ref Kapton® film.

Facile preparation of optically transparent and hydrophobic cellulose nanofibril composite films

2015 ◽  
Vol 77 ◽  
pp. 13-20 ◽  
Author(s):  
Yan Qing ◽  
Zhiyong Cai ◽  
Yiqiang Wu ◽  
Chunhua Yao ◽  
Qinglin Wu ◽  
...  
Keyword(s):  
Composite Films ◽  
Cellulose Nanofibril ◽  
Optically Transparent ◽  
Facile Preparation

scholarly journals A Dual-Crosslinked and Anisotropic Regenerated Cellulose/Boron Nitride Nanosheets Film With High Thermal Conductivity, Mechanical Strength, and Toughness

2020 ◽  
Vol 8 ◽  
Author(s):  
Xuran Xu ◽  
Yichuan Su ◽  
Yongzheng Zhang ◽  
Shuaining Wu ◽  
Kai Wu ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Boron Nitride ◽  
Mechanical Strength ◽  
Heat Dissipation ◽  
Composite Films ◽  
Regenerated Cellulose ◽  
Wearable Electronics ◽  
Mechanical Fracture ◽  
Boron Nitride Nanosheets ◽  
Mechanical Performances

The highly thermo-conductive but electrically insulating film, with desirable mechanical performances, is extremely demanded for thermal management of portable and wearable electronics. The integration of boron nitride nanosheets (BNNSs) with regenerated cellulose (RC) is a sustainable strategy to satisfy these requirements, while its practical application is still restricted by the brittle fracture and loss of toughness of the composite films especially at the high BNNS addition. Herein, a dual-crosslinked strategy accompanied with uniaxial pre-stretching treatment was introduced to engineer the artificial RC/BNNS film, in which partial chemical bonding interactions enable the effective interfiber slippage and prevent any mechanical fracture, while non-covalent hydrogen bonding interactions serve as the sacrifice bonds to dissipate the stress energy, resulting in a simultaneous high mechanical strength (103.4 MPa) and toughness (10.2 MJ/m3) at the BNNS content of 45 wt%. More importantly, attributed to the highly anisotropic configuration of BNNS, the RC/BNNS composite film also behaves as an extraordinary in-plane thermal conductivity of 15.2 W/m·K. Along with additional favorable water resistance and bending tolerance, this tactfully engineered film ensures promised applications for heat dissipation in powerful electronic devices.

Scalable fabrication of free-standing, stretchable CNT/TPE ultrathin composite films for skin adhesive epidermal electronics

2018 ◽  
Vol 6 (25) ◽  
pp. 6666-6671 ◽  
Author(s):  
Yun Liang ◽  
Peng Xiao ◽  
Shuai Wang ◽  
Jiangwei Shi ◽  
Jiang He ◽  
...  
Keyword(s):  
Human Health ◽  
Composite Films ◽  
Wearable Electronics ◽  
Free Standing ◽  
Human Machine Interfaces ◽  
Potential Applications ◽  
Epidermal Electronics

Wearable electronics have drawn extensive interest on account of their potential applications in smart human–machine interfaces, wearable human-health monitors and mimicking biological organs.

Improving the bending resistance of double-layer printed flexible OLEDs with PEDOT: PSS-PEO composite HIL films

2021 ◽  
Author(s):  
Yan Wang ◽  
Dongyu Zhang ◽  
Qiang Gao
Keyword(s):  
Composite Films ◽  
Hole Injection ◽  
Radius Of Curvature ◽  
Wearable Electronics ◽  
Transparent Conductive Electrode ◽  
Display Devices ◽  
Solution Blending ◽  
Bending Resistance ◽  
Mechanical Durability ◽  
Poly Styrene Sulfonate

Abstract Flexible organic light-emitting diodes (OLEDs) are expected to have excellent device performance and mechanical robustness in many areas, such as wearable electronics and display devices. For the traditional materials of OLED anode, ITO is undoubtedly the most mature transparent conductive electrode available. However, the brittle and rigid nature of ITO severely limit the development of flexible OLED. In this work, a solution blending film consisting of poly (3,4 ethylenedioxythiophene): poly (styrene sulfonate) (PEDOT: PSS) and poly (ethylene oxide) (PEO) was used as a hybrid hole injection layer, where PEO polymer in the composite films can greatly improve the bending resistance of device. The printed flexible OLEDs doped with PEO exhibit impressive mechanical durability, maintaining 80.4% of its maximum external quantum efficiency after 1000 bends at a radius of curvature of 10 mm, compared to 46.3% for the counterpart without PEO doping.

scholarly journals Modulating Carrier Type for Enhanced Thermoelectric Performance of Single-Walled Carbon Nanotubes/Polyethyleneimine Composites

Polymers ◽  
2019 ◽  
Vol 11 (8) ◽  
pp. 1295 ◽  
Author(s):  
Xiao-Xi Peng ◽  
Xuan Qiao ◽  
Shuai Luo ◽  
Jun-An Yao ◽  
Yun-Fei Zhang ◽  
...  
Keyword(s):  
Carrier Transport ◽  
Film Formation ◽  
Maximum Output Power ◽  
Composite Films ◽  
Open Circuit ◽  
Maximum Output ◽  
Wearable Electronics ◽  
Single Walled Carbon ◽  
Potential Applications ◽  
Mixing Techniques

Thermoelectric (TE) generators consisting of flexible and lightweight p- and n-type single-walled carbon nanotube (SWCNT)-based composites have potential applications in powering wearable electronics using the temperature difference between the human body and the environment. Tuning the TE properties of SWCNTs, particularly p- versus n-type control, is currently of significant interest. Herein, the TE properties of SWCNT-based flexible films consisting of SWCNTs doped with polyethyleneimine (PEI) were evaluated. The carrier type of the SWCNT/PEI composites was modulated by regulating the proportion of SWCNTs and PEI using simple mixing techniques. The as-prepared SWCNT/PEI composite films were switched from p- to n-type by the addition of a high amount of PEI (>13.0 wt.%). Moreover, interconnected SWCNTs networks were formed due to the excellent SWNT dispersion and film formation. These parameters were improved by the addition of PEI and Nafion, which facilitated effective carrier transport. A TE generator with three thermocouples of p- and n-type SWCNT/PEI flexible composite films delivered an open circuit voltage of 17 mV and a maximum output power of 224 nW at the temperature gradient of 50 K. These promising results showed that the flexible SWCNT/PEI composites have potential applications in wearable and autonomous devices.

scholarly journals Lead-Free Bi3.15Nd0.85Ti3O12 Nanoplates Filler-Elastomeric Polymer Composite Films for Flexible Piezoelectric Energy Harvesting

Micromachines ◽  
2020 ◽  
Vol 11 (11) ◽  
pp. 966
Author(s):  
Wancheng Qin ◽  
Peng Zhou ◽  
Yajun Qi ◽  
Tianjin Zhang
Keyword(s):  
Energy Harvesting ◽  
Mechanical Energy ◽  
Short Circuit ◽  
Composite Films ◽  
Short Circuit Current ◽  
Lead Free ◽  
Piezoelectric Energy Harvesting ◽  
Wearable Electronics ◽  
Light Emitting ◽  
Piezoelectric Energy

Nowadays, wearable and flexible nanogenerators are of great importance for portable personal electronics. A flexible piezoelectric energy harvester (f-PEH) based on Bi3.15Nd0.85Ti3O12 single crystalline nanoplates (BNdT NPs) and polydimethylsiloxane (PDMS) elastomeric polymer was fabricated, and high piezoelectric energy harvesting performance was achieved. The piezoelectric output performance is highly dependent on the mass ratio of the BNdT NPs in the PDMS matrix. The as-prepared f-PEH with 12.5 wt% BNdT NPs presents the highest output voltage of 10 V, a peak-peak short-circuit current of 1 μA, and a power of 1.92 μW under tapping mode of 6.5 N at 2.7 Hz, which can light up four commercial light emitting diodes without the energy storage process. The f-PEHs can be used to harvest daily life energy and generate a voltage of 2–6 V in harvesting the mechanical energy of mouse clicking or foot stepping. These results demonstrate the potential application of the lead-free BNdT NPs based f-PEHs in powering wearable electronics

Dislocations, Ordering and Antiferromagnetic Domains in MnO

1970 ◽  
Vol 28 ◽  
pp. 522-523
Author(s):  
D. J. Barber ◽  
R. G. Evans
Keyword(s):  
Electron Diffraction ◽  
Single Crystal ◽  
Optical Microscopy ◽  
Defect Chemistry ◽  
Magnetic Structures ◽  
Optically Transparent ◽  
Magnetic Features ◽  
Antiferromagnetic Domains

Manganese (II) oxide, MnO, in common with CoO, NiO and FeO, possesses the NaCl structure and shows antiferromagnetism below its Neel point, Tn∼ 122 K. However, the defect chemistry of the four oxides is different and the magnetic structures are not identical. The non-stoichiometry in MnO2 small (∼2%) and below the Tn the spins lie in (111) planes. Previous work reported observations of magnetic features in CoO and NiO. The aim of our work was to find explanations for certain resonance results on antiferromagnetic MnO.Foils of single crystal MnO were prepared from shaped discs by dissolution in a mixture of HCl and HNO3. Optical microscopy revealed that the etch-pitted foils contained cruciform-shaped precipitates, often thick and proud of the surface but red-colored when optically transparent (MnO is green). Electron diffraction and probe microanalysis indicated that the precipitates were Mn2O3, in contrast with recent findings of Co3O4 in CoO.

Sign in / Sign up

Export Citation Format

Share Document