Navigation Links
Reversible doping: Hydrogen flips switch on vanadium oxide
Date:5/21/2012

uing because the detailed physics of the material are still not well understood, and theoretical models alone cannot give us the answers," said Natelson, professor of physics and astronomy and of electrical and computer engineering at Rice. "Experiments are key to understanding this."

In 2010, Natelson and postdoctoral research associate Jiang Wei began to systematically study the phase changes in VO2. Wei and graduate student Heng Ji began by using a process called vapor deposition to grow VO2 wires that were about 1,000 times smaller than a human hair. One set of experiments on wires that had been baked in the presence of hydrogen gas returned particularly odd readings. Wei, Ji and Natelson determined that the hydrogen was apparently modifying the VO2 nanowires, but only those in contact with metal electrodes.

"The gold electrodes we were using to supply current to the experiment were acting as a catalyst that split the hydrogen gas molecules into atomic hydrogen, which could then diffuse into channels in the VO2," Natelson said. "It appears that the hydrogen is taken up into the VO2 crystals, and this changes their electronic properties. If a little hydrogen is added, the phase transition happens at a slightly lower temperature, and the insulating phase becomes more conductive. If enough hydrogen is added, the transition to the insulating phase disappears altogether."

To gain insight into just how the hydrogen is able to alter the transition, the experimenters consulted with theoretical physicist Andriy Nevidomskyy, assistant professor of physics and astronomy at Rice. Nevidomskyy's calculations showed that the hydrogen changes the amount of charge in the VO2 material and also forces the crystal to expand slightly. Both of these effects favor the metallic state.

This is not the first time physicists have lowered the transition temperature of VO2 by adding other materials -- a technique known as "doping." But Natelson said Rice'
'/>"/>

Contact: David Ruth
david@rice.edu
713-348-6327
Rice University
Source:Eurekalert

Page: 1 2 3

Related biology technology :

1. American Heart Association Late-Breaking Clinical Trial Report: New Reversible Antiplatelet Drug no More Effective Than Irreversible One in PCI
2. WuXi AppTec Selects H-Cube from ThalesNano for Laboratory-based Hydrogenation
3. Gold-palladium nanoparticles achieve greener, smarter production of hydrogen peroxide
4. New Website Offers Fuel Saving Products Such as Hydrogen Injection Systems and Hydrogen Generators
5. Researchers create catalysts for use in hydrogen storage materials
6. Industry Leaders Will Gather to Discuss the Future of the "Hydrogen Economy" in Washington DC
7. New clues about a hydrogen fuel catalyst
8. Researchers show applied electric field can significantly improve hydrogen storage properties
9. UT Knoxville and ORNL researchers turn algae into high-temperature hydrogen source
10. Helping hydrogen: Student inventor tackles challenge of hydrogen storage
11. Layered graphene sheets could solve hydrogen storage issues
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:10/1/2014)... San Francisco, California (PRWEB) October 01, 2014 ... grant from the National Science Foundation to expand their ... approaches to build and modify DNA. The Small Business ... help commercialize the “j5” technology under exclusive license from ... the Joint BioEnergy Institute , an LBNL laboratory ...
(Date:10/1/2014)... , October 1, 2014 ... software invited to engage around the theme, ,Commercial Opportunities ...   Elsevier , a ... and services, will host a gathering of some of ... and trends impacting healthcare today and in the future. ...
(Date:9/30/2014)... This news release is available in German . ... at the Technische Universitt Mnchen (TUM) have demonstrated a ... Their experiments show that future computer chips could be ... transistors. As the main enabling technology of the semiconductor ... fundamental limits, the TUM researchers and collaborators at the ...
(Date:9/30/2014)... YORK , Sept. 30, 2014 ... and segments with highest potential revenues Do you ... updated report gives you revenue predictions for those ... For those therapies you find financial data, R&D ... analysis you get sales forecasts to 2024 at ...
Breaking Biology Technology:TeselaGen Receives $750k NSF SBIR Phase II Award 2TeselaGen Receives $750k NSF SBIR Phase II Award 3Elsevier Healthcare and Pharmaceutical Economics Conference 2014 To Convene Industry Leaders to Discuss Top Healthcare Business Issues 2Elsevier Healthcare and Pharmaceutical Economics Conference 2014 To Convene Industry Leaders to Discuss Top Healthcare Business Issues 3A new dimension for integrated circuits: 3-D nanomagnetic logic 2A new dimension for integrated circuits: 3-D nanomagnetic logic 3Biosimilars and Follow-On Biologics: World Industry and Market Prospects 2014-2024 2Biosimilars and Follow-On Biologics: World Industry and Market Prospects 2014-2024 3Biosimilars and Follow-On Biologics: World Industry and Market Prospects 2014-2024 4Biosimilars and Follow-On Biologics: World Industry and Market Prospects 2014-2024 5
... made of clay and a bit of high-grade plastic draws oil ... lab tests show that oil absorbed can be squeezed back out ... the material, called an aerogel, believe it will effectively clean up ... and roadways, rivers and oceans. , The EPA estimates that 10 ...
... Feb. 4, 2010 -- Four Oak Ridge National Laboratory ... five-year research grants as part of the Department of ... million program, funded under the American Recovery and Reinvestment ... to support exceptional researchers during the crucial early career ...
... , , IPSWICH, Mass. ... to the Wellcome Trust Sanger Institute, New England Biolabs is ... England Biolabs as one of its suppliers for next-generation sequencing ... "We are extremely pleased that the Wellcome Trust Sanger Institute, ...
Cached Biology Technology:New material absorbs, conserves oil 24 ORNL researchers selected for Recovery Act early career funds 24 ORNL researchers selected for Recovery Act early career funds 3Wellcome Trust Sanger Institute to use NEBNext(TM) DNA Sample Preparation Reagents from New England Biolabs for Next Generation Sequencing 2
(Date:9/30/2014)... do seedless watermelon, salmon, and strawberries all have in ... two sets of chromosomes and are diploid, these organisms ... sets of chromosomesseedless watermelon and salmon have 3 and ... While this might seem surprising, in fact most ... first discovered over a century ago, but only recently, ...
(Date:9/30/2014)... A team of environmental scientists and engineers, led ... awarded a three-year, $5.25 million grant from the ... Competitive Research to make a direct positive impact ... remediation and disposal of radioactive contaminants. , "Understanding ... adequately dealing with environmental aspects of nuclear technologies ...
(Date:9/30/2014)... is available in German . ... the most expensive foods in the world. Because they grow ... But the distinctive smell of truffles is not only of ... under the direction of the Goethe University Frankfurt have discovered ... soil bacteria which are trapped inside truffle fruiting bodies. , ...
Breaking Biology News(10 mins):Gene doubling shapes the world: Instant speciation, biodiversity, and the root of our existence 2Gene doubling shapes the world: Instant speciation, biodiversity, and the root of our existence 3Gene doubling shapes the world: Instant speciation, biodiversity, and the root of our existence 4Researchers get $5.25 million to advance nuclear technologies in South Carolina 2On the trail of the truffle flavor 2
... The biggest ever single UK public investment in bioenergy ... main funding agency for the biosciences the Biotechnology ... 27M BBSRC Sustainable Bioenergy Centre has been launched to ... and emerging UK sustainable bioenergy sector and to ...
... Switzerland, Jan. 26 SVOX, the leading provider ... the Professional,Speech Processing Group of Siemens AG, according ... speech technology-related IP of Siemens AG developed,over 25 ... more than 60 patent families. The majority of ...
... Spring Harbor Laboratory (CSHL) announced today the discovery of ... time, they reported that their discovery suggests the presence ... in which these and possibly other small RNAs are ... project called ENCODE, also provided information concerning the biological ...
Cached Biology News:Biggest ever public investment in bioenergy to help provide clean, green and sustainable fuels 2SVOX Acquires Speech Processing Unit of Siemens AG, Expands Into Speech Recognition and Speech Dialog 2CSHL scientists find a new class of small RNAs and define its function 2CSHL scientists find a new class of small RNAs and define its function 3
Request Info...
Our original highly-purified, robust Taq Polymerase which delivers consistently high yields and minimal background...
Recombinant DNA polymerase from Thermus aquaticus expressed in E. coli; 5 units/L; 1 tube of 1, 000 units enzyme/tube w/Buffer II and MgCl2...
Taq DNA Polymerase (T. aquaticus), 4 x 250 units. For PCR and other procedures requiring DNA polymerase activity at elevated temperatures. Category: Nucleotides & Enzymes & Biochemicals, Modifying En...
Biology Products: