scholarly journals A Brief Overview of Electrochromic Materials and Related Devices: A Nanostructured Materials Perspective

Nanomaterials ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 2376
Author(s):  
Aleksei Viktorovich Shchegolkov ◽  
Sung-Hwan Jang ◽  
Alexander Viktorovich Shchegolkov ◽  
Yuri Viktorovich Rodionov ◽  
Anna Olegovna Sukhova ◽  
...  
Keyword(s):  
Nanostructured Materials ◽  
Sol Gel ◽  
Smart Window ◽  
Electrochromic Materials ◽  
Smart Windows ◽  
Advantages And Disadvantages ◽  
Light Modulators ◽  
Light Filters ◽  
Modern Analysis ◽  
Materials Used

Exactly 50 years ago, the first article on electrochromism was published. Today electrochromic materials are highly popular in various devices. Interest in nanostructured electrochromic and nanocomposite organic/inorganic nanostructured electrochromic materials has increased in the last decade. These materials can enhance the electrochemical and electrochromic properties of devices related to them. This article describes electrochromic materials, proposes their classification and systematization for organic inorganic and nanostructured electrochromic materials, identifies their advantages and shortcomings, analyzes current tendencies in the development of nanomaterials used in electrochromic coatings (films) and their practical use in various optical devices for protection from light radiation, in particular, their use as light filters and light modulators for optoelectronic devices, as well as methods for their preparation. The modern technologies of “Smart Windows”, which are based on chromogenic materials and liquid crystals, are analyzed, and their advantages and disadvantages are also given. Various types of chromogenic materials are presented, examples of which include photochromic, thermochromic and gasochromic materials, as well as the main physical effects affecting changes in their optical properties. Additionally, this study describes electrochromic technologies based on WO3 films prepared by different methods, such as electrochemical deposition, magnetron sputtering, spray pyrolysis, sol–gel, etc. An example of an electrochromic “Smart Window” based on WO3 is shown in the article. A modern analysis of electrochromic devices based on nanostructured materials used in various applications is presented. The paper discusses the causes of internal and external size effects in the process of modifying WO3 electrochromic films using nanomaterials, in particular, GO/rGO nanomaterials.

Physicochemical Properties of Advanced Nanostructured Materials for Dental Microimplant Coatings

2017 ◽  
Vol 68 (9) ◽  
pp. 2052-2054
Author(s):  
Georgeta Zegan ◽  
Daniela Anistoroaei ◽  
Loredana Golovcencu ◽  
Eduard Radu Cernei ◽  
Cristina Gena Dascalu ◽  
...  
Keyword(s):  
Metal Oxides ◽  
Nanostructured Materials ◽  
Antimicrobial Agents ◽  
Sol Gel ◽  
Antimicrobial Effect ◽  
Oral Diseases ◽  
Morphological Studies ◽  
Composition Structure ◽  
Materials Used ◽  
Implant Coatings

An important aspect of orthodontic microimplants is represented by biocompatibility and avoidance of infection development at living tissue surrounding it. Therefore, nanotechnology has the ability to improve this issue by coating microimplants with metal oxides type nanomaterials possessing antimicrobial effect. Some features of advanced nanostructured materials used as implant coatings, such as composition, structure, specific surface area, porosity, shape and size are factors that make them suitable as antimicrobial agents. The present work deals with the structural and morphological studies of ZnO and TiO2 nanoparticles used to combat oral diseases. Coating microimplants with nanosized titanium oxide (TiO2) and zinc oxide (ZnO) may improve conditions for osseointegration in accordance with preventing oral infection. These metal oxides nanopowders were synthesized using sol-gel method. Structural and morphological investigation were carried out by XRD and FTIR spectra, SEM-EDX and TEM images respectively. XRD and FTIR analyses confirmed metal oxides crystallization and metal oxide bonds. SEM-EDX and TEM features confirmed elemental composition of these nanoparticles and their textural characteristics such as shape, size, porosity and agglomeration degree.

scholarly journals Yttrium Oxide Nanoparticle Synthesis: An Overview of Methods of Preparation and Biomedical Applications

2021 ◽  
Vol 11 (5) ◽  
pp. 2172
Author(s):  
Govindasamy Rajakumar ◽  
Lebao Mao ◽  
Ting Bao ◽  
Wei Wen ◽  
Shengfu Wang ◽  
...  
Keyword(s):  
Yttrium Oxide ◽  
Metal Oxide Nanoparticles ◽  
Sol Gel ◽  
Antioxidant Properties ◽  
Nanoparticle Synthesis ◽  
Synthetic Methods ◽  
Host Material ◽  
Solid State Reactions ◽  
Oxide Nanoparticles ◽  
Advantages And Disadvantages

Metal oxide nanoparticles demonstrate uniqueness in various technical applications due to their suitable physiochemical properties. In particular, yttrium oxide (Y2O3) nanoparticle is familiar for technical applications because of its higher dielectric constant and thermal stability. It is widely used as a host material for a variety of rare-earth dopants, biological imaging, and photodynamic therapies. Y2O3 has also been used as a polarizer, phosphor, laser host material, and in the optoelectronic fields for cancer therapy, biosensor, and bioimaging. Yttrium oxide nanoparticles have attractive antibacterial and antioxidant properties. This review focuses on the promising applications of Y2O3, its drawbacks, and its modifications. The synthetic methods of nanoparticles, such as sol-gel, emulsion, chemical methods, solid-state reactions, combustion, colloid reaction techniques, and hydrothermal processing, are recapitulated. Herein, we also discuss the advantages and disadvantages of Y2O3 NPs based biosensors that function through various detection modes including colorimetric, electrochemistry, and chemo luminescent regarding the detection of small organic chemicals, metal ions, and biomarkers.

scholarly journals High-Efficiency Responsive Smart Windows Fabricated by Carbon Nanotubes Modified by Liquid Crystalline Polymers

Crystals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 440
Author(s):  
Yuan Deng ◽  
Shi-Qin Li ◽  
Qian Yang ◽  
Zhi-Wang Luo ◽  
He-Lou Xie
Keyword(s):  
Carbon Nanotubes ◽  
Liquid Crystalline ◽  
Near Infrared ◽  
High Efficiency ◽  
Polymer Brush ◽  
Light Transmittance ◽  
Smart Window ◽  
Vertical Orientation ◽  
Smart Windows ◽  
Conversion Materials

Smart windows can dynamically and adaptively adjust the light transmittance in non-energy or low-energy ways to maintain a comfortable ambient temperature, which are conducive to efficient use of energy. This work proposes a liquid crystal (LC) smart window with highly efficient near-infrared (NIR) response using carbon nanotubes grafted by biphenyl LC polymer brush (CNT-PDB) as the orientation layer. The resultant CNT-PDB polymer brush can provide the vertical orientation of LC molecules to maintain the initial transparency. At the same time, the smart window shows a rapid response to NIR light, which can quickly adjust the light transmittance to prevent sunlight from entering the room. Different from common doping systems, this method avoids the problem of poor compatibility between the LC host and photothermal conversion materials, which is beneficial for improving the durability of the device.

scholarly journals Full-frame and high-contrast smart windows from halide-exchanged perovskites

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
You Liu ◽  
Jungan Wang ◽  
Fangfang Wang ◽  
Zhengchun Cheng ◽  
Yinyu Fang ◽  
...  
Keyword(s):  
Contrast Ratio ◽  
High Contrast ◽  
Smart Window ◽  
Frame Size ◽  
Smart Windows ◽  
Ideal Solutions ◽  
Ion Gel ◽  
And Control ◽  
Colour Rendering ◽  
Perovskite Photovoltaic

AbstractWindow glazing plays an essential role to modulate indoor light and heat transmission, which is a prospect to save the energy cost in buildings. The latest photovoltachromic technology has been regarded as one of the most ideal solutions, however, to achieve full-frame size (100% active area) and high-contrast ratio (>30% variable in visible wavelength) for smart window applicability is still a challenge. Here we report a photovoltachromic device combining full-transparent perovskite photovoltaic and ion-gel based electrochromic components in a vertical tandem architecture without any intermediated electrode. Most importantly, by accurately adjusting the halide-exchanging period, this photovoltachromic module can realize a high pristine transmittance up to 76%. Moreover, it possesses excellent colour-rendering index to 96, wide contrast ratio (>30%) on average visible transmittance (400-780 nm), and a self-adaptable transmittance adjustment and control indoor brightness and temperature automatically depending on different solar irradiances.

Preparation of catalyst as Au doped Mn1Co9Ox/ceramic system for total oxidation of CO

2021 ◽  
Vol 10 (4) ◽  
pp. 39-45
Author(s):  
Phuong Pham Thi Mai ◽  
Hoan Nguyen Quoc ◽  
Quan Do Quoc ◽  
Hung Nguyen Thanh
Keyword(s):  
Sol Gel ◽  
Active Phase ◽  
Catalyst System ◽  
Oxidation Of Co ◽  
Sem Images ◽  
Total Oxidation ◽  
Wet Impregnation ◽  
Modern Analysis ◽  
Catalyst Powder ◽  
Xrd Patterns

In this paper, the Au doped Mn1Co9Ox was investigated for total oxidation of CO. The sol-gel method was applied to prepare this catalyst and some modern analysis methods as XRD, EPR, TPx, SEM were utilized to characterize its properties. The XRD patterns showed only Co3O4 phase without any peaks belonging to Mn or Au. However, the presence of Au and Mn was confirmed by EPR and O2-TPD results. With the aim to further apply catalyst in reality, the Au doped Mn1Co9Ox was deposited on ceramic by sol-gel, wet impregnation. The SEM images displayed the successful coating of active phase on substrate. However, the complete catalyst system didn’t have the high activity in total CO oxidation like the catalyst powder because of large agglomerations on coatings.

PROMISING METHODS FOR PRODUCTION OF ELECTROCHROMIC DEVICES BASED ON NANOSTRUCTURED COATINGS (review)

2021 ◽  
pp. 99-108
Author(s):  
P.A. Shchur ◽  
◽  
L.V. Solovyanchik ◽  
S.V. Kondrashov ◽  
◽  
...  
Keyword(s):  
Tungsten Oxide ◽  
Science And Technology ◽  
Nanostructured Coatings ◽  
Electrochromic Devices ◽  
Electrochromic Materials ◽  
Electrochromic Properties ◽  
Modern Methods ◽  
Materials Used

Paper presents the most common materials for nanostructured inorganic electrochromic coatings, describes the methods of their formation. The prospects for the use of electrochromic materials in various industries – construction, auto and aircraft construction are considered. The analysis of modern methods for the formation of nanostructured electrochromic materials used in various fields of science and technology is presented. The prospects for the use of tungsten oxide, as well as the possibility of its modification in order to improve its functional electrochromic properties, are shown.

Fabrication and Characterization of Sol-Gel Derived PZT/WO3 Ceramics

2008 ◽  
Vol 55-57 ◽  
pp. 369-372 ◽  
Author(s):  
T. Sreesattabud ◽  
Anucha Watcharapasorn ◽  
Sukanda Jiansirisomboon
Keyword(s):  
Lead Zirconate Titanate ◽  
Sol Gel ◽  
Rhombohedral Phase ◽  
Lead Zirconate ◽  
X Ray Diffraction ◽  
Calcination Process ◽  
Materials Used ◽  
Phase Characterization ◽  
Gel Processing

Lead zirconate titanate/tungsten oxide (PZT/WO3) ceramics were prepared from the powders synthesized by a modified triol sol-gel processing method. In this study, the starting materials used for synthesis of PZT-sol were zirconium (IV) propoxide, titanium (IV) isopropxide, lead (II) acetate trihydrate and 1,1,1,- tris (hydroxymethyl) ethane. To prepare PZT/xWO3 powders (where x = 0, 0.5, 1 and 3 wt%), nano-sized WO3 was ultrasonically dispersed and mixed with the PZT sol, dried and calcined at 600°C for 4 h. X-ray diffraction results indicated that fully crystallized powders were obtained. Phase characterization suggested that at high WO3 concentration, the reaction between PZT and WO3 occurred during the calcination process. To prepare PZT/xWO3 ceramics, the powders were pressed and sintered at 1100°C for 6 h. Phase characterization by XRD indicated that the content of WO3 significantly affected tetragonal-to-rhombohedral phase transition. Microstructure of thermally etched samples showed that increasing the content of WO3 decreased grain size of the ceramics.

scholarly journals Comparison contact and thermal imaging methods measure the temperatures of the turning blades during cutting

Mechanik ◽  
2017 ◽  
Vol 90 (3) ◽  
pp. 214-216
Author(s):  
Karol Grochalski ◽  
Piotr Jabłoński
Keyword(s):  
Tool Wear ◽  
Thermal Imaging ◽  
Cutting Tool ◽  
Processing Parameters ◽  
Machining Process ◽  
Influence Of Temperature ◽  
Imaging Methods ◽  
Advantages And Disadvantages ◽  
Influence Of Temperature On ◽  
Materials Used

The paper presents a method of measuring the temperature during cutting and its impact on the machining process. The influence of temperature on the intensity of the cutting tool wear cutting and durability. Shows the measuring position, the materials used and the cutting tool. We present the results of the processing parameters, during which the measurements are made. This paper presents methods for measuring the temperature of the blade using a thermocouple and methods of radiation. It lists the advantages and disadvantages of each method.

scholarly journals Analysis of methods for measuring the dielectric properties of materials in the microwave range of wavelengths.

2021 ◽  
Author(s):  
D.G. Fomin ◽  
◽  
N.V. Dudarev ◽  
S.N. Darovskikh ◽  
◽  
...  
Keyword(s):  
Dielectric Properties ◽  
Communication Systems ◽  
Electronic Devices ◽  
Microwave Range ◽  
Advantages And Disadvantages ◽  
Microwave Electronic ◽  
Functional Features ◽  
Properties Of Materials ◽  
Materials Used ◽  
Resonant Method

One of the modern trends in the development of communication systems, information and telecommunication systems, air traffic control systems, etc. is the transition and development of higher-frequency wavelength ranges. In this regard more and more stringent requirements (in terms of spectrum, out-of-band and spurious radio emission, and in the shape of the output signal) are imposed on radio engineering devices that transmit and receive microwave radio signals. As a result, the requirements for the design and functional features of microwave electronic devices are increasing. One of these requirements is to assess the degree of compliance with the required values of dielectric properties of materials used in the design of microwave electronic devices. This requirement is justified by the fact that the electrical parameters of such microwave devices as: strip filters, power dividers, printed antennas and others, directly depend on the dielectric properties of the materials used in their substrate designs. In this regard, three main methods have now emerged for assessing the dielectric properties of materials: the resonant method, the non-resonant method, and the free space method. Aim. The aim of this article is to carry out a comparative analysis of the known methods for measuring the dielectric properties of materials in the microwave range of wavelengths and devices for their implementation. Materials and methods. The authors of the article reviewed the scientific literature of domestic and foreign publications. Results. For each of the methods for measuring the dielectric properties of materials, their main idea, practical implementation, a mathematical model for processing experimental data and areas of application are given. The advantages and disadvantages for each of the methods for measuring the dielectric properties of materials are given too. Conclusion. The applicability of each of the considered methods depends on such factors as: the shape of the investigated dielectric material, its state of aggregation, the possibility of measuring amplitude or complex transmission and reflection coefficients, the presence of an anechoic chamber, etc.

scholarly journals Influence of mild Cr3+ doping on the structural, optical, photochromic, and thermochromic reversibility of nano-titania systems

2019 ◽  
Vol 97 (4) ◽  
pp. 347-354 ◽  
Author(s):  
Rizwin Khanam ◽  
Dambarudhar Mohanta
Keyword(s):  
Band Gap ◽  
Anatase Phase ◽  
Sol Gel ◽  
Average Crystallite Size ◽  
Incident Radiation ◽  
Optical Absorption Spectroscopy ◽  
Smart Windows ◽  
Cell Parameters ◽  
Doped Titania ◽  
Reversible Thermochromism

We report on the effect of chromium doping on the band gap lowering of nano-titania (TiO2) and subsequent implications as regards coloration characteristics mediated via photochromism and thermochromism processes. As can be found in the X-ray diffractograms, the sol-gel derived, Cr3+-doped nano-TiO2 systems have exhibited an anatase phase with the evidence of peak shifting towards a lower diffraction angle. The average crystallite size decreases, whereas lattice unit cell parameters and, consequently, cell volume, tend to increase with the inclusion of Cr3+ into the titania host. To be specific, 1% Cr-doped titania system showed nearly 5.8% cell expansion as compared to its un-doped counterpart. As revealed from the optical absorption spectroscopy, a narrowing of band gap is observed for the Cr doped nano-titania system: 3.18 eV for the un-doped system, and 2.61 and 2.41 eV for 0.3% and 1% Cr doping cases, respectively, considering direct band-to-band transitions. Moreover, doping led noticeable lowering of the exponent (n value), from its normal value, which suggests inclusion of adequate non-parabolicity feature to the energy band scheme. The photochromic feature, for a given incident radiation, demonstrates a lowered transmission response with increasing Cr content. A reversible thermochromism response has also been demonstrated for doped nano-titania systems subjected to heating with temperature varying between 0–55 °C. The Cr3+ doped nano-titania and similar systems would find scope in smart windows, display components, photocatalysis, etc., when a select coloration is desired.

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