Electronic Materials

14 pages, 1343 KiB

Open AccessFeature PaperArticle

Extending the Color Retention of an Electrochromic Device by Immobilizing Color Switching and Ion-Storage Complementary Layers

by Monika Wałęsa-Chorab and William G. Skene

Electron. Mater. 2020, 1(1), 40-53; https://0-doi-org.brum.beds.ac.uk/10.3390/electronicmat1010005 - 14 Dec 2020

Cited by 3 | Viewed by 2886

Abstract

The thermal polymerization of a bis(triphenylamine)-bis(styrene) monomer on ITO coated glass gave an electroactive film that underwent two stepwise oxidations. The perceived color change of the film upon stepwise oxidation was colorless-to-yellow followed by yellow-to-blue. The anodic cyclic voltammogram of the monomer was [...] Read more.

The thermal polymerization of a bis(triphenylamine)-bis(styrene) monomer on ITO coated glass gave an electroactive film that underwent two stepwise oxidations. The perceived color change of the film upon stepwise oxidation was colorless-to-yellow followed by yellow-to-blue. The anodic cyclic voltammogram of the monomer was consistent over multiple cycles. The immobilized film could be reversibly switched between its colorless and blue states with applied potential in both a half- and full-electrochromic functioning device. The devices could also reversibly switch their colors upwards of 6 h. The retention of the electrochemically induced blue color was contingent on the device architecture. Upwards of 80% of the color was maintained 30 min after the potential was turned off with the double-layer electrochromic device structure. This device was prepared from two electroactive layers: a bis(triphenylamine) and viologen-based polymers that were immobilized on the electrodes. In contrast, 50% of the color of the active electrochromic device that was prepared from a single electroactive layer bleached 7 min once the potential was no longer applied. Full article

(This article belongs to the Special Issue Feature Papers of Electronic Materials)

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12 pages, 3462 KiB

Open AccessArticle

Coating 1-Octanethiol-Coated Copper Nano-Ink on a Paper Substrate via Multi-Pulse Flash Light Sintering for Application in Disposable Devices

by Yeonho Son, Dongho Shin, Minkyu Kang and Caroline Sunyong Lee

Electron. Mater. 2020, 1(1), 28-39; https://0-doi-org.brum.beds.ac.uk/10.3390/electronicmat1010004 - 23 Sep 2020

Cited by 1 | Viewed by 2937

Abstract

Inkjet-printed patterns were formed on a paper substrate using anti-oxidant copper nano-ink for application to disposable electronic devices. To prevent substrate damage, the pattern was flash light sintered under ambient conditions using the multi-pulse technique. Pure copper nanoparticles were coated with 1-octanethiol for [...] Read more.

Inkjet-printed patterns were formed on a paper substrate using anti-oxidant copper nano-ink for application to disposable electronic devices. To prevent substrate damage, the pattern was flash light sintered under ambient conditions using the multi-pulse technique. Pure copper nanoparticles were coated with 1-octanethiol for oxidation resistance using the dry-coating method. Mixing these with 1-octanol solvent at a concentration of 30 wt% produced the copper nano-ink. Photo paper was used as the substrate. The contact angle between the photo paper and copper nano-ink was 37.2° and the optimal energy density for the multi-pulse flash light sintering technique was 15.6 J/cm². Using this energy density, the optimal conditions were an on-time of 2 ms (duty cycle of 80%) for three pulses. The resistivity of the resulting pattern was 2.8 × 10⁻⁷ Ω∙m. After bending 500 times to a radius of curvature of 30 mm, the relative resistance (ΔR/R₀) of the multi-pulse flash light-sintered pattern hardly changed compared to that of the unbent pattern, while the single-pulse-sintered pattern showed dramatic increase by 8-fold compared to the unbent pattern. Therefore, the multi-pulse light sintering technique is a promising approach to produce an inkjet-printed pattern that can be applied to disposable electronic devices. Full article

(This article belongs to the Special Issue Feature Papers of Electronic Materials)

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11 pages, 3379 KiB

Open AccessEditor’s ChoiceArticle

Synthesis and Characterization of Aero-Eutectic Graphite Obtained by Solidification and Its Application in Energy Storage: Cathodes for Lithium Oxygen Batteries

by Ricardo Walter Gregorutti, Alvaro Yamil Tesio, Juan Luis Gómez-Cámer and Alicia Norma Roviglione

Electron. Mater. 2020, 1(1), 17-27; https://0-doi-org.brum.beds.ac.uk/10.3390/electronicmat1010003 - 03 Sep 2020

Cited by 1 | Viewed by 2709

Abstract

Aero-eutectic graphite can be defined as a new light material with hierarchically structured porosity. It is obtained from the solidification of gray cast irons, followed by the dissolution of the ferrous matrix by an acidic sequence. The result is a continuous and interconnected [...] Read more.

Aero-eutectic graphite can be defined as a new light material with hierarchically structured porosity. It is obtained from the solidification of gray cast irons, followed by the dissolution of the ferrous matrix by an acidic sequence. The result is a continuous and interconnected network of graphite sheets with varied dimensions randomly oriented. X-ray diffraction characterization has revealed graphite crystallographic planes (002), (100), (101), (102) and (004), while the surface area measured by BET and Langmuir methods has been determined in the order of 90 m² g⁻¹ and 336 m² g⁻¹, respectively. The process of obtaining eutectic aero-graphite also allows the deposit of Cu nanofilms and TiC particles. Aero-eutectic graphite has been tested as cathode in Li–O₂ batteries as it has been prepared, without the addition of binders or conductive carbons, showing an appropriate contact with the electrolyte, so that the oxygen reduction and evolution reactions may develop satisfactorily. In the discharge-charge galvanostatic tests, the battery accomplishes 20 complete cycles with area capacity limited to 1.2 mAh cm⁻². Full article

(This article belongs to the Special Issue Advanced Design and Synthesis of Electrode Materials)

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15 pages, 5497 KiB

Open AccessArticle

Evaluation of Standard Electrical Bonding Strategies for the Hybrid Integration of Inkjet-Printed Electronics

by Lukas Rauter, Johanna Zikulnig, Taulant Sinani, Hubert Zangl and Lisa-Marie Faller

Electron. Mater. 2020, 1(1), 2-16; https://0-doi-org.brum.beds.ac.uk/10.3390/electronicmat1010002 - 30 Aug 2020

Cited by 11 | Viewed by 3564

Abstract

Different conductive bonding strategies for the hybrid integration of flexible, inkjet-printed electronics are investigated. The focus of the present work lies on providing a practical guide comprising standard techniques that are inexpensive, easily implementable and frequently used. A sample set consisting of identical [...] Read more.

Different conductive bonding strategies for the hybrid integration of flexible, inkjet-printed electronics are investigated. The focus of the present work lies on providing a practical guide comprising standard techniques that are inexpensive, easily implementable and frequently used. A sample set consisting of identical conductive test structures on different paper and plastic substrates was prepared using silver (Ag) nanoparticle ink. The sintered specimens were electrically contacted using soldering, adhesive bonding and crimping. Electrical and mechanical characterization before and after exposing the samples to harsh environmental conditions was performed to evaluate the reliability of the bonding methods. Resistance measurements were done before and after connecting the specimens. Afterwards, 85 °C/85% damp-heat tests and tensile tests were applied. Adhesive bonding appears to be the most suitable and versatile method, as it shows adequate stability on all specimen substrates, especially after exposure to a 85 °C/85% damp-heat test. During exposure to mechanical tensile testing, adhesive bonding proved to be the most stable, and forces up to 12 N could be exerted until breakage of the connection. As a drawback, adhesive bonding showed the highest increase in electrical resistance among the different bonding strategies. Full article

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