Navigation Links
Uniform tungsten trimers stand and deliver

Like tiny nano-soldiers on parade, the cyclic tungsten trioxide clusters line up molecule-by-molecule on the titanium dioxide platform. One tungsten atom from each cluster is raised slightly, holding forth the potential to execute catalytic reactions.

The nanostructures constitute a new model system, a simplified version of a catalyst that would be used in an application. Such models reveal to chemists the exact structure and reaction mechanisms of metal oxides.

Developed by researchers from the Department of Energy's Pacific Northwest National Laboratory, the University of Texas-Austin and Washington State University, the discovery may offer a platform for fundamental reactivity studies of metal oxides used as catalysts in converting hydrocarbons into fuels and value-added chemicals.

"There is a striking difference between commercial catalysts and the new model system," said Mike White, the UT professor leading the PNNL Institute for Interfacial Catalysis. Variability in commercial catalyst size and chemical composition makes it difficult to accurately understand or describe the reactions taking place at a molecular level.

"Commercial catalysts are like a gravel pile with many sizes of rocks. Some rocks are purple; some are blue. Some do one thing; some do another. But, our system has all the same size rocks," White said.

The model system ?in which all the molecular clusters are the same size, are evenly dispersed and are oriented in one of two directions on a single layer of titanium oxide crystals ?holds promise as a platform for studying the behavior of early transition metal oxides. White noted, "While we have created the smallest nano-cluster of a uniform size you can imagine, it is a real oxide. The tungsten is in its normal oxide state. In principle, you have all the things needed to make bonds and break bonds. That's the scientific breakthrough here."

Though it appears simple, the model system was challengin g to develop, White said. The collaborators employed specialized equipment available from the William R. Wiley Environmental Molecular Sciences Laboratory, a DOE user facility located at PNNL, to prepare and characterize the platform as well as the clusters. Using a unique approach that changed the tungsten oxide directly from a solid to a gas, the collaborators stabilized the molecular rings ?or "trimers" ?of tungsten on the titanium platform.

A scanning tunneling microscope imaged not only the trimers but also their consistent alignment with the single crystal structure of the platform. "A scanning tunneling microscope must be so stable that we have to vibrationally isolate the instrument. It cannot move even a small amount because we are using a stream of electrons to measure the distance from the microscope's tip to a small space between atoms," White explained. The collaborators also characterized the cluster mass, determined the ratio of tungsten to oxygen atoms in the cluster, and used X-ray photoelectron spectroscopy to identify the tungsten oxidation state.

"This is a small piece of the basic science that could lead to control of chemical transformations for our energy future," White said, noting that this is the first time researchers have created and imaged monodisperse oxide clusters on another oxide.


'"/>

Source:DOE/Pacific Northwest National Laboratory


Related biology news :

1. Uniform language for describing genes of pathogenic and beneficial microbes
2. UCSB scientists probe sea floor venting to gain understanding of early life on Earth
3. Zebrafish may hold key to understanding human nerve cell development
4. Novel ultrafast laser detection of cancer cells also may improve understanding of stem cells
5. Expression Project for Oncology (expO) completes first phase of standardized gene expression analyses
6. Researchers make gains in understanding antibiotic resistance
7. Brain-mapping technique aids understanding of sleep, wakefulness
8. New understanding of DNA repair may pave way to cancer treatments
9. NYU and MSKCC research provides model for understanding chemically induced cancer initiation
10. The circadian clock: Understanding natures timepiece
11. Virologists make major step towards understanding the process of HIV infection
Post Your Comments:
*Name:
*Comment:
*Email:


(Date:4/28/2016)... Sweden , April 28, 2016 First ... M (139.9), up 966% compared with the first quarter of 2015 ... profit totaled SEK 589.1 M (loss: 18.8) and the operating margin ... 7.12 (loss: 0.32) Cash flow from operations was SEK ... The 2016 revenue guidance is unchanged, SEK 7,000-8,500 M. ...
(Date:4/15/2016)... CHICAGO , April 15, 2016  A ... companies make more accurate underwriting decisions in a ... offering timely, competitively priced and high-value life insurance ... health screenings. With Force Diagnostics, rapid ... and lifestyle data readings (blood pressure, weight, pulse, ...
(Date:3/31/2016)... 31, 2016   ... the "Company") LegacyXChange is excited to release ... soon to be launched online site for trading 100% ... ) will also provide potential shareholders a sense of ... to an industry that is notorious for fraud. The ...
Breaking Biology News(10 mins):
(Date:6/27/2016)... ... June 27, 2016 , ... Cancer ... what they believe could be a new and helpful biomarker for malignant pleural ... Click here to read it now. , Biomarkers are components in the ...
(Date:6/27/2016)... NC (PRWEB) , ... June 27, 2016 , ... ... mission to bring innovative medical technologies, services and solutions to the healthcare market. ... and implementation of various distribution, manufacturing, sales and marketing strategies that are necessary ...
(Date:6/27/2016)... PHILADELPHIA , June 27, 2016  Liquid ... today announced the funding of a Sponsored Research ... study circulating tumor cells (CTCs) from cancer patients.  ... changes in CTC levels correlate with clinical outcomes ... therapies. These data will then be employed to ...
(Date:6/24/2016)... -- Regular discussions on a range of subjects including policies, debt ... said Poloz. Speaking at a lecture to the ... pointed to the country,s inflation target, which is set by ... "In certain areas there needs to ... goals, why not sit down and address strategy together?" ...
Breaking Biology Technology: