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1.
Michael D. Ward 《Journal of Solid State Electrochemistry》2005,9(11):778-787
Redox-active transition-metal complexes which show strong changes in their electronic spectra in the near-infrared (NIR) region
in different oxidation states are attracting increasing interest as NIR electrochromic dyes for electro-optic switching at
the wavelengths used for silica-based optical telecommunications networks. This brief review surveys recent work in the field
based on ruthenium(II)-dioxolene, tris(pyrazolyl)borato-molybdenum(V) and mixed-valence Ru(II)-Ru(III) complexes, which all
show strong NIR electrochromism and have been incorporated into prototypical devices such as the variable optical attenuator
by attachment to transparent electrodes, either by adsorption or polymerisation. 相似文献
2.
The electrochromic materials have received immense attention for the fabrication of smart optoelectronic devices. The alteration of the redox states of the electroactive functionalities results in the color change in response to electrochemical potential. Even though transition metal oxides, redox-active small organic molecules, conducting polymers, and metallopolymers are known for electrochromism, advanced materials demonstrating multicolor switching with fast response time and high durability are of increasing demand. Recently, two-dimensional covalent organic frameworks (2D COFs) have been demonstrated as electrochromic materials due to their tunable redox functionalities with highly ordered structure and large specific surface area facilitating fast ion transport. Herein, we have discussed the mechanistic insights of electrochromism in 2D COFs and their structure-property relationship in electrochromic performance. Furthermore, the state-of-the-art knowledge for developing the electrochromic 2D COFs and their potential application in next-generation display devices are highlighted. 相似文献
3.
Guan-Yu Chen Bo-Ren Chang Ting-An Shih Chien-Hsiang Lin Chieh-Liang Lo Yan-Zhi Chen You-Xuan Liu Yu-Ru Li Jin-Ting Guo Chin-Wei Lu Zu-Po Yang Hai-Ching Su 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(21):5489-5497
Solid-state near-infrared (NIR) light-emitting devices have recently received considerable attention as NIR light sources that can penetrate deep into human tissue and are suitable for bioimaging and labeling. In addition, solid-state NIR light-emitting electrochemical cells (LECs) have shown several promising advantages over NIR organic light-emitting devices (OLEDs). However, among the reported NIR LECs based on ionic transition-metal complexes (iTMCs), there is currently no iridium-based LEC that displays NIR electroluminescence (EL) peaks near to or above 800 nm. In this report we demonstrate a simple method for adjusting the energy gap between the highest-occupied molecular orbital (HOMO) and the lowest-unoccupied molecular orbital (LUMO) of iridium-based iTMCs to generate NIR emission. We describe a series of novel ionic iridium complexes with very small energy gaps, namely NIR1 – NIR6 , in which 2,3-diphenylbenzo[g]quinoxaline moieties mainly take charge of the HOMO energy levels and 2,2′-biquinoline, 2-(quinolin-2-yl)quinazoline, and 2,2′-bibenzo[d]thiazole moieties mainly control the LUMO energy levels. All the complexes exhibited NIR phosphorescence, with emission maxima up to 850 nm, and have been applied as components in LECs, showing a maximum external quantum efficiency (EQE) of 0.05 % in the EL devices. By using a host–guest emissive system, with the iridium complex RED as the host and the complex NIR3 or NIR6 as guest, the highest EQE of the LECs can be further enhanced to above 0.1 %. 相似文献
4.
《Journal of polymer science. Part A, Polymer chemistry》2018,56(1):147-153
The design rules for creating multifunctional organic electronic materials are currently limited. By copolymerizing twisted triphenylamine (TPA) and electron rich dioxythiophene (XDOT) monomers via Direct (Hetero) Arylation Polymerization (DHAP), a set of polymers are obtained that perform as yellow to transmissive electrochromic (EC) films with up to 45% contrast, as well as in electroluminescent (EL) applications, achieving a luminance of ∼450 cd/m2 in yellow‐green polymer light‐emitting diodes (PLEDs). In addition, polymerizing TPA with a donor‐acceptor‐donor monomer results in a low‐bandgap polymer that achieves power conversion efficiencies up to 2.5% when blended with PC71BM in conventional organic photovoltaic (OPV) devices. Incorporation of TPA units into the polymer backbone largely breaks any aggregation and ordering in the solid‐state, leading to highly soluble materials that form smooth, reproducible thin films. The TPA unit also serves to break conjugation throughout the polymer backbone, providing precise control over optical and electronic properties through choice of comonomer. These results suggest that TPA copolymers can be useful for achieving multi‐functionality without sacrificing facile solution processability, making them promising candidates for multifunctional devices like dual EC/EL displays. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018 , 56, 147–153 相似文献
5.
Selin Pıravadılı Ceylan Doyranlı Sinem Altınısık Hakan Bilgili Betül Canımkurbey Sermet Koyuncu 《Journal of polymer science. Part A, Polymer chemistry》2021,59(16):1829-1840
Since limited examples are in the literature in which both organic light-emitting diodes (OLEDs) and electrochromic (EC) applications were performed using the same conjugated polymer, we presented comprehensive EC and electroluminescence (EL) studies of fluorene-based electroactive polymer (e.g., CFP6) consisting of a bicarbazole pendant moiety with quinoxaline as an acceptor bridge. CFP6 was synthesized by a Suzuki cross-coupling polymerization reaction and utilized as an active and emissive layers of the electrochromic device (ECD) and OLED, respectively, due to its high photoluminescence quantum yield intensity and fine thin film forming capability. The optical, electrochemical, cyclic voltammetry measurements, and density functional theory calculations were realized. Electrochemical cross-linking process was applied over the electroactive carbazole subunit of the CFP6 polymer. After the crosslinking process, EC performance was greatly improved. On the other hand, light emission and EL characteristics of OLEDs based on CFP6 emissive layer were realized in detail with six different device architectures to understand light output profile behavior. As a result, CFP6 emitted bright greenish yellow emission with a maximum brightness of 1777 cd/m2 at 215 mA/cm2 in the indium tin oxide (ITO)/poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS)/CFP6:%10 4,4′-bis(N-carbazolyl)-1,1′-biphenyl (CBP)/Alq3/LiF/Al device architecture. 相似文献
6.
Ionic liquids can be made intrinsically electrochromic and magnetic through the appropriate combination of electrochromic and magnetic anions based on ethylenediaminetetraacetic metal complexes, combined with several organic cations. These novel and highly multi-functional materials encompass the peculiar properties of ionic liquids together with the characteristics of electrochromic and magnetic materials. 相似文献
7.
《Electrochemistry communications》2008,10(6):895-898
A facile approach of carbon nanotubes (CNTs) functionalized poly(methylpyrrole) [pMPy] electrosynthesized in hydrophobic ionic liquid for fabrication of electrochromic (EC) devices is discussed. Clear change from brown (oxidized) to pale yellow (neutral) color is demonstrated with robust cycle life. This synthesis route can be exploited to fabricate polymers from other organic conjugated systems and provide an avenue for applications requiring stable redox polymers in electrochromic devices. 相似文献
8.
A star network polymer with a pentaerythritol core linking four PEG-block polymeric arms was synthesized, and its corresponding gel polymer electrolyte based on lithium perchlorate and plasticizers EC/PC with the character being colorless and highly transparent has been also prepared. The polymer host was characterized and confirmed to be of a star network and an amorphous structure by FTIR, ^1H NMR and XRD studies. The polymer host hold good mechanical properties for pentaerythritol cross-linking. Maximum ionic conductivity of the prepared polymer electrolyte has reached 8.83 × 10 ^-4 S·cm^-1 at room temperature. Thermogravimetry (TG) of the polymer electrolyte showed that the thermal stability was up to at least 150 ℃. The gel polymer electrolyte was further evaluated in electrochromic devices fabricated by transparent PET-ITO and electrochromically active viologen derivative films, and its excellent performance promised the usage of the gel polymer electrolyte as ionic conductor material in electrochrornic devices. 相似文献
9.
Zhongqiu Tong Yanlong Tian Hongming Zhang Xingang Li Junyi Ji Huiying Qu Na Li Jiupeng Zhao Yao Li 《中国科学:化学(英文版)》2017,60(1):13-37
Multifunctional devices integrated with electrochromism and energy storage or energy production functions are attractive because these devices can be used as an effective approach to address the energy crisis and environmental pollution in society today. In this review, we explain the operation principles of electrochromic energy storage devices including electrochromic supercapacitors, electrochromic batteries, and the photoelectrochromic devices. Furthermore, the material candidates and structure types of these multifunctional devices are discussed in detail. The major challenges of these devices along with a further outlook are highlighted at the end. 相似文献
10.
11.
Ghoorchian Arash Madrakian Tayyebeh Afkhami Abbas Bagheri Hasan 《Journal of Solid State Electrochemistry》2021,25(4):1217-1229
Journal of Solid State Electrochemistry - The increasing efforts devoted to fabricating electrochromic (EC) devices have motivated a lot of studies to develop new EC materials. Herein, we introduce... 相似文献
12.
Watanabe Y Nakamura K Kobayashi N 《Physical chemistry chemical physics : PCCP》2011,13(43):19420-19426
We studied the electrochromic (EC) and electrochemiluminescent (ECL) properties of a novel dual-mode display (DMD) cell that was enabled for reflective and emissive modes of representation by introducing both EC and ECL materials into an electrochemical cell. We fabricated EC, ECL, and DMD cells based on a simple-mixture solution or modified electrodes and compared their properties to clarify the advantage of a DMD system based on modified electrodes. Both the solution- and modified electrode-based DMDs showed EC properties in the reflective mode under dc bias application and ECL properties in the emissive mode under ac bias application. Although the solution-based DMD cell featured a very simple structure, some improvements related to side reaction and quenching reaction were required. The modified electrode-based DMD cell was fabricated to improve these aspects. The advantage of the DMD model based on the modified electrodes was certainly suggested by comparisons of the results with those of EC, ECL, and DMD cells based on a simple-mixture solution. 相似文献
13.
Polymer electrochromism has been considered one of the liveliest branches of conducting polymer research, a tradition continued in the last decade. We have witnessed numerous significant advances, making commercial applications closer than ever. This feature article highlights these advances by separating them into 3 sections. The material design section emphasizes the new molecular structures that have been utilized as electrochromic materials and their promising results. The color control of polymeric electrochromics section focuses on the recent achievements towards realization of full color electrochromic display devices, lastly the advances en route commercial applications section demonstrates how some of the major drawbacks towards commercialization have been successfully addressed. 相似文献
14.
A new complementary electrochromic device (ECD) based on Prussian blue (PB), indium hexacyanoferrate (InHCF), and KCl-saturated
poly(2-acrylamido-2-methylpropanesulfonic acid) (K-PAMPS) was proposed and studied in this work. This novel PB-InHCF ECD (PIECD)
exhibits blue-to-yellowish electrochromism with a high coloration efficiency of ca. 103 cm2/C at 690 nm. Although the operating voltages for the fully bleached and fully colored states were determined to be 1.2 V
and 0 V (InHCF vs. PB), respectively, the major transmittance modulation occurs within a much narrower voltage window (0.9 V↔0.5 V).
That is, the PIECD is energetically favorable. Furthermore, it is unnecessary to precolor either electrochromic (EC) electrode
during the cell assembly so that the charge balance between two electrochromic films becomes much easier. In addition to the
above performance, the compatibility between the K-PAMPS electrolyte and EC electrodes was also demonstrated. In short, this
work proposes another promising PB-based ECD and provides a new choice in the EC field.
Electronic Publication 相似文献
15.
A. Gonçalves C. Costa S. Pereira N. Correia M. M. Silva P. C. Barbosa L. C. Rodrigues I. Henriques R. Martins E. Fortunato 《先进技术聚合物》2012,23(4):791-795
This paper reports the application of a polymethacrylate hydroxyethylene resin based electrolyte in electrochromic (EC) devices. The electrolyte is characterized by electrochemical impedance spectroscopy, visible spectroscopy, TGA, DSC, and DRX and tested as an ionic conductor in an EC device with the following configuration: Substrate/IZO/WO3/Polymer Electrolyte/(CeO2)TiO2/IZO/Substrate. The electrolyte presents an ionic conductivity of 10?7 S/cm at room temperature and TGA analysis show that electrolyte is thermally degraded at 200°C. The EC device based on this polymethacrylate hydroxyethylene resin electrolyte system shows memory effect and exhibits an excellent optical density. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
16.
稀土有机电致发光研究进展 总被引:20,自引:4,他引:16
介绍了近年来有机电致发光研究中稀土有机电致发光研究的动态,对稀土有机配合物的选择、配合物的载流子传输性能、稀土有机电致发光器件、电致发光与光致发光的关系以及如何提高电致发光器件亮度等问题进行了讨论。 相似文献
17.
R. R. Kharade S. R. Mane R. M. Mane P. S. Patil P. N. Bhosale 《Journal of Sol-Gel Science and Technology》2010,56(2):177-183
Tungsten oxide thin films, which are cathodic coloration materials that are used in electrochromic devices, were prepared
by a chemical growth method and their electrochromic properties were investigated. The thin films of WO3 were deposited onto electrically conducting substrates: fluorine doped tin oxide coated glass (FTO) with sheet resistance
of about 10 Ω/cm. Transparent, uniform and strongly adherent thin film samples of WO3 were studied for their structural, morphological, optical and electrochromic properties. The XRD data confirmed the monoclinic
crystal structure of WO3 thin films. The direct band gap Eg for the films was found to be 2.95 eV which is good for electrochromic device application.
The electrochromism of WO3 thin film was evaluated in 0.5 M LiClO4/propylene carbonate for Li+ intercalation. Electrochromic properties of WO3 thin films were studied with the help of Cyclic Voltammetry (CV), Chronoamperometry (CA) and Chronocoulometry (CC) techniques. 相似文献
18.
A centrosymmetric polymer precursor, namely 6‐(2,5‐di(thiophen‐2‐yl)‐1H‐pyrrol‐1‐yl)hexan‐1‐amine (TPHA), was synthesized via a Knorr–Paal reaction using 1,4‐di(2‐thienyl)‐1,4‐butanedione and hexane‐1,6‐diamine. The resultant monomer was characterized by Nuclear Magnetic Resonance (1H‐NMR). Electroactivity of TPHA was investigated via cyclic voltammetry. The electronic structure and the nature of electrochromism in P(TPHA) and its copolymer with EDOT, (P(TPHA‐co‐EDOT)), were examined via spectroelectrochemistry studies. P(TPHA) switches between claret red neutral state and blue oxidized state. Optical response times for coloring and bleaching processes of the P(TPHA) and P(TPHA‐co‐EDOT) were found as 2.1 s and 1.6 s, respectively. The copolymer of TPHA was used to construct dual type polymer electrochromic devices (ECDs) against poly(3,4‐ethylenedioxythiophene) (PEDOT). Spectroelectrochemistry and electrochromic switching out of the devices were investigated. 相似文献
19.
Ya-Han Tang Yi-Chan Chiu Dian Luo Jiun-Yi Lien Rong-Huei Yi Ching-Hsuan Lin Prof. Zu-Po Yang Prof. Chin-Wei Lu Prof. Hai-Ching Su 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(60):13668-13676
Solid-state white light-emitting electrochemical cells (LECs) show promising advantages of simple solution fabrication processes, low operation voltage, and compatibility with air-stable cathode metals, which are required for lighting applications. To date, white LECs based on ionic transition metal complexes (iTMCs) have shown higher device efficiencies than white LECs employing other types of materials. However, lower emission efficiencies of red iTMCs limit further improvement in device performance. As an alternative, efficient red CdZnSeS/ZnS core/shell quantum dots were integrated with a blue iTMC to form a hybrid white LEC in this work. By achieving good carrier balance in an appropriate device architecture, a peak external quantum efficiency and power efficiency of 11.2 % and 15.1 lm W−1, respectively, were reached. Such device efficiency is indeed higher than those of the reported white LECs based on host–guest iTMCs. Time- and voltage-dependent electroluminescence (EL) characteristics of the hybrid white LECs were studied by means of the temporal evolution of the emission-zone position extracted by fitting the simulated and measured EL spectra. The working principle of the hybrid white LECs was clarified, and the high device efficiency makes potential new white-emitting devices suitable for solid-state lighting technology possible. 相似文献
20.
Transition-metal chemistry in ionic liquids (IL) has achieved intrinsic fascination in the last few years. The use of an IL as environmental friendly solvent, offers many advantages over traditional materials synthesis methods. The change from molecular to ionic reaction media leads to new types of materials being accessible. Room-temperature IL have been found to be excellent media for stabilising transition-metal clusters in solution and to crystallise homo- and heteronuclear transition-metal complexes and clusters. Furthermore, the use of IL as solvent provides the option to replace high-temperature routes, such as crystallisation from the melt or gas-phase deposition, by convenient room- or low-temperature syntheses. Inorganic IL composed of alkali metal cations and polynuclear transition-metal cluster anions are also known. Each of these areas will be discussed briefly in this contribution. 相似文献