Tungsten Oxide

As common energy storage devices, batteries play a key role in our daily life. Modern batteries are no longer characterized by the simple purpose of energy storage, but with designed multi-functionality as one of the hot topics and development directions of the battery research. A new-style electrochromic battery has been conceived which enables the highly desired convenient user-device interface based on a friendly human-readable output. However, the field of combination between the technology of battery and electrochromism is still rather young with many unsolved problems. For example, the specific capacity that the electrochromic battery delivers is rather low and the battery device needs a very long time for self-charging (12 hours). Therefore, exploring smart electrochromic battery with high performances is undoubtedly a worthwhile field of inquiry, and various solutions for building electrochromic batteries with new device configurations are eagerly needed. T...

Nanostructures such as nanowires, nanorods, nanotubes of metal oxide semiconductor (MO S ) materials have recently attracted monumental interest in gas-sensing applications because of their excellent performances owing to their large surface to vol-ume ratio, lower electron recombination rate and high stability. Among various MO S  materials, tungsten oxide (WO 3 ) is a highly promising candidate due to its fast response with high sensitivity toward NO x . Glancing angle depositio (GLAD) technique is a relatively new method for fabrication of well-ordered and sophisticated nanostructures i.e. nanorods, nanoblade and zigzag nanocolumns. It is a modified physical vapor deposition process, in which substrate surface is rotated and tilted to an angle greater than 80° with respect to the normal of substrate surface or less than 10°with respect to the direction of vapor flux. The vapor molecules directed to the substrate will experience shadowing and limited surface diffusion condi...

Ozonolysis is of great interest to synthetic organic chemistry because it is one of the most efficient tools for oxidatively cleaving carbon-carbon double bonds. Ozonolysis is generally used to prepare biologically active molecules. Therefore, the reactions between ozone and organic compounds continue to be a subject of significant interest from mechanistic, synthetic, and environmental perspectives. The importance of O 3  reactions with alkenes in the troposphere and solution has led to many experimental and theoretical studies of their kinetics and mechanism. Scientists addresses tungsten oxide nanoparticle syntheses for use as a catalyst in the novel one-step synthesis of malonic acid ester. Malonic acid ester is directly synthesized and esterified via the ozonolysis of palm olein (palm oil fraction), which comprises 10% linoleic acid as an unsaturated fatty acid. The main advantages of using tungsten oxide nanoparticles as the catalyst for this esterification are to short...

Tungsten oxide , also known as tungsten trioxide or tungstic anhydride, WO3, is a chemical compound containing oxygen and the transition metal tungsten. It is obtained as an intermediate in the recovery of tungsten from its minerals. The tungsten oxide nanoparticles can be applied in many areas. They can be used in colorant and analysis reagent of chinaware,  used in producing metal tungsten material, gas sensors,  fire-proofing fabrics, imaging; large-area displays, catalysts; ceramic pigments; humidity sensors, infrared switching devices; high-density memory devices and so on. Orthorhombic tungsten oxide (o-WO 3 ) thin films, stabilized by nanocrystalline anatase TiO 2 , are obtained by a sol–gel based two stage dip coating method and subsequent annealing at 600℃. An Organically Modified Silicate (ORMOSIL) based templating strategy is adopted to achieve porosity. An asymmetric electrochromic device is construc...

Metal oxide semiconductors (MOS) have been utilized as gas sensing active materials for half a century. One of the most promising solid-state MO S  chemo sensors is n-type semiconducting tungsten oxide-based  gas  sensor.  They  have  demonstrated  novel sensing  properties  such  as  high  sensitivity,  fast response  time  and  low  operation  temperature.  In particular,  pure  or  doped  tungsten  oxide  is  a  promising material for the detection of various substances, e.g., H 2 ,H 2 S,NOx, NH 3  and ethanol. Scientists have investigated  the sensing characteristics  of  WO 3  nanoparticles  to H 2 S  in  the 7 to 200 ppm range at working temperatures of the range of 100–225 ℃.  Semiconductor  gas  sensors  based  on nanocrystalline  WO 3   powders  were ...

Tungsten carbide is a chemical compound containing equal parts of tungsten and carbon atoms. In the tungsten carbide powder, carbon atoms will embed in the interstice of tungsten metal lattice, which will not destroy the lattice of original metal and will form interstitial solid solution. Therefore, it can be also called interstitial compound or insertion compound, which is mainly used in producing cemented carbide due to its high hardness. As tungsten carbide powder has large application range, it has given rise to the waves of researching the preparation of tungsten carbide powder. Violet tungsten oxide can be used in producing tungsten carbide powder, this is because it has single-crystal structure, abundant crack as well as its interior is composed by loose needle-like or rod like particles, which will be beneficial for making tungsten carbide powder that has superior quality. In the preparation of tungsten carbide powder by violet tungsten oxide , violet tungsten ox...

The invention relates to the use of tungsten oxide or tungstate to increase the heat-input amount of near infrared radiation. It was found that these materials exhibit a distinct higher effect than other known Infrared Radiation(IR) absorbers although absorbing the same amount of energy. This is very surprising and cannot be explained so far. Tungsten bronzes incorporated in coatings led to a much higher temperature increase upon irradiation with IR than expected according to its spectral absorption capacity. The temperature increasing measured was distinctly higher than found with other known IR absorbers and reached almost the temperature observed with carbon black. Many technical processes (like laser welding and marking of plastics, Near Infrared Radiation(NIR) curing and drying of coatings, drying of printings, laser marking of paper, curing and drying of adhesives, fixing of ink toners to a substrate, heating of plastic pre-forms etc.) require an efficient, quick and fo...

Tungsten oxide is one of the mostly studied cathodic coloring electrochromic material. Electrochromic property of WO3 has been made into different electrochromic device and is applied in real life. There are many advantages of electrochromic device, transmittance can change continuously in a wide range and can be adjusted manually. A B.C. engineering lab has created metal-coated glass that transmits up to 10 per cent more light than conventional glass and opens the door to windows that function as electronics. The most immediate use of the technology is to create smart window that can be programmed to absorb or reflect heat, depending on the needs of a building’s occupants, said lead investigator Kenneth Chau, a professor at the University of British Columbia Okanagan. “What’s interesting about this discovery is that it’s counterintuitive, because we always think of metals as being opaque, so it runs against our expectations,” he said. “I think one of the most important implicatio...

Tungsten Oxide Market: Emerging Applications and Drivers Tungsten oxide has several everyday uses. It is used in the manufacture of tungstates for fireproofing fabrics, for x-ray screen phosphors, and in gas sensors. Tungsten trioxide is also used as a pigment in coatings, paints, and ceramics due to its rich yellow color. In addition, tungsten trioxide has also proven useful in the production of smart windows or electro chromic windows. Smart windows are essentially electrically switchable glass that can alter its light transmission properties when a certain voltage is applied. This allows the user to obtain the desired level of tint on their windows by deciding how much light they want passing through. The growth in end user industries is expected to increase consumption of tungsten oxide. The growth in medical and firefighting industry is set to drive the tungsten oxide market. In addition, rising consumption of semi-conducting compounds in emerging economies of Asia Pacific ...

A new material that emits short-wavelength thermal radiation when heated could be used in systems that convert waste heat into electrical energy thus boost waste heat harvesting. Created by an international team co-led by researchers at Purdue University, the University of Alberta and Hamburg University of Technology, the material comprises alternating layers of 20 nm of tungsten oxide and 100 nm of hafnium oxide. Tungsten oxide is a chemical compound containing oxygen and the transition metal tungsten. It is obtained as an intermediate in the recovery of tungsten from its minerals. Tungsten ores are treated with alkalis to produce WO3. It is insoluble in H2O and acids, but soluble in hot alkalis. It is n type semiconductor material, the special physical and chemical property make it used in various filed and become the important functional material in modern scientific research. The structure was chosen so that the emission of long-wavelength infrared photons fr...

Doping is commonly used to improve visible light responsive of transition metal oxide. A lot of researches show that metal ion like rare earth can promote the photocatalytic property of semiconductor material, however, metal doping may cause thermal stability of catalyst decreasing, it will introduce photo electron and recombination center of valance to lower its photoelectric property. Doping N can greatly improve the visible light absorption rate of semiconductor material. Preparing of nanoporous tungsten oxide  electrode: 1) Treating method for tungsten foil: Firstly cut it into 10mm x 15mm pieces, using waterproof abrasive to polish it, then clean it with acetone, isopropanol, methyl alcohol and deionized water ultrasound cleaning for 15min, blow it with nitrogen gas. 2) Use tungsten foil as anode, Pt foil of 10 x 15mm as counter electrode, put them into electrobath, the distance between two electrodes is 25mm. Then put electrobath in water bath of constant temperature,...

Tungsten oxide has excellent performance in electrochromic, catalysis, gas and other aspects. The composite oxides - tungsten bronze metal oxides generally refer darker colored metallic luster, and usually a metal conductor or metal semiconductor. Currently, cesium tungsten oxide, due to its low resistance and excellent visible light transmittance and near-infrared shielding properties, is widely used in the preparation of the conductive film used in glass septum thermal insulation coating. The traditional preparation method of cesium tungsten oxide uses tungsten, tungsten acid source, Cs/W molar ratio of 1: (2.857~100), at 180~200°C reaction conditions for 1~3 days. The preparation takes a long reaction period, is of low efficiency, which is not conducive to industrial production. A process for preparing cesium tungsten oxide ultrafine powder, comprising the steps of: (1) In accordance with Cs / W molar ratio of 1: (1.5 to 2.8), weigh cesium salt and tungsten salt. A ch...

Warn-out tungsten oxide including tungsten trioxide and blue tungsten oxide ect. which have been scrapped, and substandard thus must be reworked. This warn-out tungsten oxide which can not directly be used in tungsten smelting or other industries can be recycling. In this paper we will present a method for recovering ammonium paratungstate from warn-out tungsten oxide. 1. Handling the raw material Screen the warn-out tungsten oxide by a 60~80 mesh sieve to remove caking tungsten oxide and mechanical inclusions; then the grinding caking tungsten oxide and also screen it; 2. Autoclaving with ammonia for preparing ammonium tungstate solution 1) Dilute the concentrated ammonia in deionized water or use water to absorb liquid ammonia, get ammonia with concentrate of 8~20%; and then formulating the slurry with stirring at the ratio that weight of tungsten oxide: volume of ammonia is 150~350g/L; 2) Add hydrogen peroxide when the material contains blue tungsten oxide, compress the k...

Cesium is a golden yellow metal, low melting point active metal, easily oxidized in air and can react violently with water to produce hydrogen and even explode. There is no elemental form of cesium in nature, cesium minimal distribution in the ocean in the form of cesium salt. Cesium tungsten bronze is widely used because of its low resistance, excellent visible light transmittance, near-infrared shielding properties. Also it is widely used in preparing conductive thin film, since being the glass transparent insulation coating as insulating agent, it has excellent properties like low resistance, excellent visible light transmittance and near-infrared shielding performance. The article provides a method that using ammonium paratungstate and cesium nitrate as raw materials to produce Cesium-tungsten oxide ultrafine powder, the specific steps are as follows: 1. Weighing the cesium nitrate, ammonium paratungstate by the molar ratio of Cs/W being 1: (1.5 to 2.8), and adding chelating agent ...

Nano semiconductor material used as photocatalyst to photolysis water has gained well efficiency. TiO 2  has high catalytic activity and stability is widely used as a kind of photocatalytic material. But its band gap is big (~3.2 eV), it can only be motivated by ultraviolet with short wave length, its light transaction efficiency is low (~4%). Tungsten oxide is an indirect band series transition semiconductor material. Compared to TiO 2 , it has narrow band gap (2.5~3.0 eV), the relevant absorbing wave length is 410~500nm and well photoelectric responsive property in visible light area. Tungsten oxide thin film electrode preparation method: Raw material: FTO glass; tungstic acid; hydrogen peroxide; acetone. (1) Be ready with clean FTO glass as the substrate of depositing WO 3 . Cut FTO glass into 1.2cm*2.5cm pieces and clean it by ultrasound and ultraviolet. The clean and flatness of FTO substrate has big effect on adhesive force and uniformity of thin film electrode...

Interest in solar cells to capture sunlight and generate electricity is increasing due to oil energy crisis and rising concerns over global climate change. Inorganic solar cells can yield high power conversion efficiency but the expensive fabrication process makes them infeasible in common use. Instead, polymer solar cells PSCs are a good candidate because semiconducting polymers can be dissolved in common solvents and printed like inks so that economical roll-in-roll fabrication process can be realized. The photoactive layer composed of electron donating and accepting materials absorbs light and generates excitons. Then electrons and holes can be efficiently separated from each other due to the nanometer-scale interpenetrating network of electron donor and acceptor within the whole photoactive layer.3 However, a simple structure that sandwiched the photoactive layer between two electrodes anode and cathode is not perfect enough. The low efficiency of charge collection at the interfac...

While the global climate heats up, so does the conversation on sustainability and the need for alternative energy and fuel resources. Dr. Robert Mayanovic, assistant department head of physics, astronomy, and materials science at Missouri State University, brings new hope to the topic as he has helped to discover a porous metal-oxide that could potentially be used as an alternative to traditional energy and fuel resources. “Basically, we are looking for ways to develop materials that can be used in the future to harness conventional or alternate energy sources in a more sustainable fashion than what materials offer today,” said Mayanovic. “The first phase of the project is to test the stability of the materials in extreme environments.” Using a large x-ray machine called a synchrotron, which allows the materials to be probed down to the atomic level, Mayanovic and colleagues Dr. Sonal Dey of Colleges of Nanoscale Science and Engineering, and Dr. Ridwan Sakidja, associate p...