Tungsten Oxide

Product
Submicron Violet Tungsten Oxide 139

Submicron violet tungsten oxide may be used to prepare submicron tungsten powder (W powder). Cyclic Oxidation-reduction Method to Produce Submicron Tungsten Powder Step one: First reduction of violet tungsten oxide in hydrogen (H2), when temperature reached 860°C, keep it warm for 20min. Step two: Use tungsten powder obtained in step one, slowly heat it to 500°C in air, process the first oxidation when temperature reaches 500°C, and then keep it warm for 10min. Step three: Use sample of step two…

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Product
Coarse Violet Tungsten Oxide 167

Coarse violet tungsten oxide is mainly a mixture of violet tungsten oxide and blue tungsten oxide. The performance of violet tungsten oxide is significantly affected by the phase composition of violet tungsten oxide. The tungsten oxides are mainly yellow tungsten oxide (tungsten trioxide), blue tungsten oxide, violet tungsten oxide and brown tungsten oxide (tungsten dioxide). In these tungsten oxides, only the violet tungsten oxide is monocrystalline structure, and the other tungsten oxides are polycrystalline structure. So, the powder prepared from…

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Product
Fine Violet Tungsten Oxide 148

Fine violet tungsten oxide may be prepared by direct reduction of ammonium paratungstate (APT) under wet hydrogen conditions. The process is short and the equipment is simple. Adopting APT with particle size of 10μm as raw material, under the conditions of pH2O:pH2=1.7:1, the temperature is raised to 1173K in two hours, keeping 1.5h, directly reducing to obtain violet tungsten oxide with particle size of 2.2μm. The grain size of the prepared fine violet tungsten oxide depends on the factors such…

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Nano Needle-shaped Violet Tungsten Oxide 180

Nano needle-shaped violet tungsten oxide may be applied to produce nano tungsten powder and ultrafine tungsten powder by using Rayleigh instability principle and in-situ hydrogen reduction technology. Violet tungsten oxide is also a dingal nano material with many properties such as photochromicproperty, electrochromicproperty and gasochromicproperty, and it may be used in many kinds of sensors in the future. A Method for Preparing Nano Needle-shaped Violet Tungsten Oxide Raw materials: ammonium paratungstate (APT), or tungstic acid, or tungsten oxide WOx (2≤x≤3).…

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Product
High Purity BTO Powder 239

High purity BTO powder has the same determining procedures of ammonia as described in “99.9% Nano Blue Oxide”. There are several matters needing attention in this experiment. Notices of determination experiment of ammonia content in high purity BTO powder are shown as follows: 1. The order of connection of the conical flasks must not be wrong. Air should be sniffed through the long tube, and then flow out from the short tube. Otherwise, the liquid will be pumped into the…

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99.9% Blue Tungsten Oxide Nanopowder 202

99.9% blue tungsten oxide nanopowder’s quality is guaranteed by determining ammonia content to meet clients’ requirements. Therefore, people studied the determination method of ammonia in blue tungsten oxide. It has been proved by experiments and practice that the following methods may meet production control to analyze ammonia indicators in blue tungsten oxide. 1. Instruments and Reagents Four conical flasks (300ml) with double- hole rubber plugs. A flow meter cylinder. C(1/2H2SO4)=0.5mol/L H2SO4 standard solution; C(Noah)=0.5mol/L NaOH standard solution. 30% NaOH solution.…

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99.95% Blue Tungsten Oxide Nanopowder 210

99.95% blue tungsten oxide nanopowder’s NH3 content is reasonably controlled to better ensure the stable phase composition of blue tungsten oxide, which is the method for controlling the stability of BTO on phase composition since the 1990s. In the 1980s, the quality control of blue tungsten oxide producing process was based on controlling the oxygen index to ensure the stability of phase composition of blue tungsten oxide. Currently, domestic and foreign customers have different requirements for NH3 content. Some requests…

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Product
Tungsten Blue Oxide 211

Tungsten blue oxide is the full name of TBO, which is not a defined tungsten compound, but a powdery mixture of tungsten trioxide, β-tungsten oxide (blue tungsten oxide), γ-tungsten oxide (violet tungsten oxide), ammonium tungsten bronze and hydrogen tungsten bronze. And the chemical composition and physical properties of BTO are changing. TBO may be produced by calcinating ammonium paratungstate (APT) in the airtight space or under hydrogen atmosphere/hydrogen-nitrogen mixed gas. The composition of TBO varies greatly on the basis of…

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84% Yellow Tungsten Oxide 524

84% yellow tungsten oxide may be used to produce high quality ultrafine tungsten carbide (WC) powder by carbonization method. The producing processes are shown as follows: 1. Mix yellow tungsten oxide (mass fraction of 84%) and carbon (mass fraction of 16%) by mixer, and granulate to particle (grain size of 3mm) by granulator, then dry and mixed material is obtained. 2. Move material to the rotary furnace for continuous reduction/carbonization, the original material changes during the reaction: WO3→WO2.9→WO2.72→WO2.0→W→W2C→WC WO3 was…

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Micro Fine Yellow Tungsten Oxide 545

Micro fine yellow tungsten oxide’s producing method may be classified into three types including physical method, chemical method (liquid phase method) and comprehensive method in accordance with the reaction characteristics described in the theory of crystal nucleation. And the liquid phase method can be divided into precipitation method, hydrothermal method, a microemulsion method, and sol-gel method according to different producing processes. The yellow tungsten oxide is primarily prepared by controlling the crystallization process, and it mainly goes through two steps:…

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