Preparation of Carbon-Coated Tungsten Trioxide with Enhanced Photocatalytic Activity Using Ammonium Paratungstate
- Details
- Category: Tungsten Information
- Published on Sunday, 27 June 2021 17:32

image of organic pollutants emission
With the rising global energy supply and related environmental issues brough by burning of fossil fuels, various materials including nitrides, oxides, metals, metal chalcogenides and phosphides have been developed. Tungsten oxides (WOx) caught a lot interest because of their earth-abundance, highly tunable composition, high chemical stability at an appropriate pH value, and excellent electrical conductivity. Individually, WOx semiconductors has excellent performance in photocatalytic degradation of many organic pollutants.
Unfortunately, it has the drawbacks of low light adsorption and relatively narrow band gap. An effective and practical strategy is to design tungsten oxide composites with carbon. improve the photocatalytic ability by preparing the amorphous carbon-coated tungsten trioxide (WO3) with a high defect concentration. In order to overcome these disadvantages, WO3 had been doped with carbon to enhance its photocatalytic activity.
The fabrication method of carbon-coated tungsten trioxide is conducted as following procedures: All raw materials were of analytical grade and commercially available and used as received without further purification. The commercial WO3 was used for comparison.
0.01 mol ammonium paratungstate (APT), 0.24 mol ammonium nitrate (NH4NO3, ⩾ 99.0%), 0.1 mol glycine (C2H5O2N) and various contents of glucose (C6H12O6) were dissolved into deionized water, and then the solution was continuously stirred for a homogeneous state. The mixture was placed on an electrical furnace in air for thermal processing. The solution was evaporated with the formation of a gelatinous mass during heating. Upon further heating, the resultant mass swelled suddenly, accompanied by the release of a lot of gases. The whole process of swelling and combustion of gel indicates the non-explosive and self-propagating exothermic reaction, which took several minutes. The samples prepared with 0.017, 0.033, 0.05 and 0.067 mol glucose were described as G1, G2, G3 and G4, respectively.
In summary, amorphous carbon-coated tungsten oxide nanocrystals were synthesized via with enhanced photocatalytic activity is prepared using ammonium paratungstate as starting material. Carbon-coated tungsten oxide existed in the form of round particles with size of ~ 150 nm and the WO3-x nanorods with the length of ~ 20 nm and diameter of 5 nm. The synthesized carbon coated WO3 showed a considerable rate for organic degradation under UV–visible light as well as good stability. This excellent performance is attributed to the synergistic effect of the amorphous carbon and the large amounts of defects. Moreover, the material demonstrated good photocatalytic stability under visible light after 5 recycling degradation of MB.
- APT Manufacturer & Supplier, Chinatungsten Online: ammonium-paratungstate.com
- Tungsten News & Prices of China Tungsten Industry Association: www.ctia.com.cn
- Molybdenum News & Price: news.molybdenum.com.cn
- Tel.: 86 592 5129696; Fax: 86 592 5129797; Email: sales@chinatungsten.com
Synthesis Process of Eu3+:Kla(WO4)2 Red Phosphors Using APT
- Details
- Category: Tungsten Information
- Published on Sunday, 27 June 2021 11:29

SEM image of KLW powders sample
Lanthanide-doped luminescent materials have been studied extensively because of their wide applications in optoelectronic devices due to their interesting optical properties originating from the electron transitions among the 4f shell. Among these, alkali rare earth tungstates constitute a large family of inorganic compounds with the general formula ARE(MO4)2. These compounds possess tetragonal and monoclinic symmetries. Their structural diversity provides these crystals with numerous physical and chemical properties.
Fabrication of Nanosized Ammonium Paratungstate by Solid-gas Phase Reaction
- Details
- Category: Tungsten Information
- Published on Saturday, 26 June 2021 22:38

image of scheme of the digestion experiment
The ammonium paratungstate (APT) is the most important starting material in the tungsten industry, where usually its most stable APT·4H2O form is used. From APT tungsten oxides, tungsten carbides or tungsten metal can be prepared. Among others, tungsten oxides are widespread catalysts, photocatalysts, and gas sensors.
APT Utilized in Regeneration of V2O5-WO3/TiO2 SCR Catalyst
- Details
- Category: Tungsten Information
- Published on Saturday, 26 June 2021 01:56

Image of SCR catalysts
Nitrogen oxde poullution has been caught a lot attention due to its negative influence on environment. fly-ash emitted from coal combustion flue gas always carries various toxic substances, such as SO2, alkali metals and alkaline-earth metals. They tend to lower the efficiency of NOx removal and shorten the operating life-time of the SCR catalyst. V2O5-WO3/TiO2 has been greatly used in NOx removal applications.
WO3 Catalyst Being Prepared by Ammonium Paratungstate for DSSCs Applications
- Details
- Category: Tungsten Information
- Published on Saturday, 26 June 2021 01:48

FESEM image of the WO3 catalyst
Dye-sensitized solar cells (DSSCs), as a renewable energy source, have attracted considerable attention due to their unparalleled merits including low cost, choice of color, light weight, packing technology, environmental compatibility, and acceptable photoelectric conversion efficiency (PCE).
Synthesis of V2O5-WO3/Tio2 Catalysts from Ammonium Paratungstate in SCR Applications
- Details
- Category: Tungsten Information
- Published on Saturday, 26 June 2021 00:54

Image of NOx sensor
In urea-SCR of passenger Diesel vehicles, the NOx reduction step of urea-SCR is usually catalyzed by redox zeolites. Technology for stationary sources r emains to be dominated by catalysts that contain V2O5 and WO3 supported on TiO2 (anatase). They are meanwhile also applied for mobile sources, in heavy utility vehicles, where they are adapted to the different targets. Thus, V2O5-WO3/TiO2 catalysts had been synthesized from ammonium paratungstate (APT) for SCR applications.
Preparation of Sulfated WO3/SnO2 Catalysts Using APT
- Details
- Category: Tungsten Information
- Published on Friday, 25 June 2021 21:29

Image of esters being widely applied in perfumes
Many reactions in synthetic organic chemistry are acid-catalyzed reactions. These reactions include esterification, etherification, hydration, hydrolysis, alkylation, isomerization and others. Liquid-phase esterification is an important method for producing various esters. The esters are used in the manufacturing of solvents, plasticizers, plastics, leather, perfumes, and medicine.
Tungsten Copper Heat Sink in 5G High-Speed Optical Devices
- Details
- Category: Tungsten Information
- Published on Tuesday, 22 June 2021 09:42

tungsten copper heat sink image
As the development of 5G has become a trend, 5G high-speed optical devices and their heat dissipation devices have also become the focus of attention and discussion. And there is no doubt that tungsten copper heat sink has become the best choice.
Preparation of 12%W/Mt-P Catalyst Using APT for Glycerol Dehydration
- Details
- Category: Tungsten Information
- Published on Monday, 21 June 2021 22:14

Image of glycerol
The use of biodiesel is being developed to address increasing global concerns regarding the environment and sustainable development. In biodiesel production, a large quantity of glycerol is produced as a by-product. Value-added use of glycerol is important in improving the economic viability of the biodiesel industry. One attractive route is the catalytic dehydration of glycerol to the value-added intermediate acrolein, which is widely used in the synthesis of pharmaceuticals, detergents, and polymers.
Ammonium Paratungstate Applied in Niw Based Catalyst for Hydrodesulfurization of DBT
- Details
- Category: Tungsten Information
- Published on Monday, 21 June 2021 12:50

SEM image of the synthesized catalyst
Reducing the sulfur content in hydrocarbon fuels has become an important topic in catalysis due to the continuous stringent environmental legislations. In order to fulfill these requirements, one alternative is to design and develop more efficient catalysts for the hydrodesulfurization (HDS) of crude petroleum. For this reason, the well-arranged mesoporous supports based on silica as MCM-41, HMS, and SBA-15, have attracted considerable attention in the preparation of novel hydrotreating catalysts, due to their outstanding textural properties.