Nanotechnology Now







Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > Taking the Heat: Pitt Team Conquers Hurdle to Nano Devices With First Metallic Nanoparticles Resistant to Extreme Heat

Abstract:
Just as a gecko sheds its tail, metal-alloy particles endure 850 degrees Celsius by ditching weaker components, researchers report in Nature Materials.

Taking the Heat: Pitt Team Conquers Hurdle to Nano Devices With First Metallic Nanoparticles Resistant to Extreme Heat

Pittsburgh, PA | Posted on December 2nd, 2009

A University of Pittsburgh team overcame a major hurdle plaguing the development of nanomaterials such as those that could lead to more efficient catalysts used to produce hydrogen and render car exhaust less toxic. The researchers reported Nov. 29 in Nature Materials the first demonstration of high-temperature stability in metallic nanoparticles, the vaunted next-generation materials hampered by a vulnerability to extreme heat.

Götz Veser, an associate professor and CNG Faculty Fellow of chemical and petroleum engineering in Pitt's Swanson School of Engineering, and Anmin Cao, the paper's lead author and a postdoctoral researcher in Veser's lab, created metal-alloy particles in the range of 4 nanometers that can withstand temperatures of more than 850 degrees Celsius, at least 250 degrees more than typical metallic nanoparticles. Forged from the catalytic metals platinum and rhodium, the highly reactive particles work by dumping their heat-susceptible components as temperatures rise, a quality Cao likened to a gecko shedding its tail in self-defense.

"The natural instability of particles at this scale is an obstacle for many applications, from sensors to fuel production," Veser said. "The amazing potential of nanoparticles to open up completely new fields and allow for dramatically more efficient processes has been shown in laboratory applications, but very little of it has translated to real life because of such issues as heat sensitivity. For us to reap the benefits of nanoparticles, they must withstand the harsh conditions of actual use."

Veser and Cao present an original approach to stabilizing metallic catalysts smaller than 5 nanometers. Materials within this size range boast a higher surface area and permit near-total particle utilization, allowing for more efficient reactions. But they also fuse together at around 600 degrees Celsius-lower than usual reaction temperatures for many catalytic processes-and become too large. Attempts to stabilize the metals have involved encasing them in heat-resistant nanostructures, but the most promising methods were only demonstrated in the 10- to 15-nanometer range, Cao wrote. Veser himself has designed oxide-based nanostructures that stabilized particles as small as 10 nanometers.

For the research in "Nature Materials," he and Cao blended platinum and rhodium, which has a high melting point. They tested the alloy via a methane combustion reaction and found that the composite was not only a highly reactive catalyst, but that the particles maintained an average size of 4.3 nanometers, even during extended exposure to 850-degree heat. In fact, small amounts of 4-nanometer particles remained after the temperature topped 950 degrees Celsius, although the majority had ballooned to eight-times that size.

Veser and Cao were surprised to find that the alloy did not simply endure the heat. It instead sacrificed the low-tolerance platinum then reconstituted itself as a rhodium-rich catalyst to finish the reaction. At around 700 degrees Celsius, the platinum-rhodium alloy began to melt. The platinum "bled" from the particle and formed larger particles with other errant platinum, leaving the more durable alloyed particles to weather on. Veser and Cao predicted that this self-stabilization would occur for all metal catalysts alloyed with a second, more durable metal.

Veser and Cao conducted their work with support from the National Energy Technology Laboratory, the lead research and development office for the U.S. Department of Energy's (DOE) Office of Fossil Energy, as well as the DOE's Office of Basic Energy Sciences and the National Science Foundation.

####

About University of Pittsburgh
Founded in 1787 as a small, private school, the Pittsburgh Academy was located in a log cabin near Pittsburgh’s three rivers. In the more than 220 years since, the University has evolved into an internationally recognized center of learning and research.

For more information, please click here

Contacts:
Morgan Kelly
412-624-4356 (office)
412-897-1400 (cell)

Copyright © University of Pittsburgh

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

News and information

Democratizing synthetic biology: New method makes research cheaper, faster, and more accessible March 3rd, 2015

Pens filled with high-tech inks for do-it-yourself sensors March 3rd, 2015

Black phosphorus is new 'wonder material' for improving optical communication March 3rd, 2015

Heightened Efficiency in Purification of Wastewater Using Nanomembranes March 3rd, 2015

Chemistry

Chromium-Centered Cycloparaphenylene Rings as New Tools for Making Functionalized Nanocarbons February 24th, 2015

Stretch and relax! -- Losing 1 electron switches magnetism on in dichromium February 23rd, 2015

A straightforward, rapid and continuous method to protect MOF nanocrystals against water February 9th, 2015

Research shows benefits of silicon carbide for sensors in harsh environments: Advantages identified across industries February 9th, 2015

Possible Futures

European roadmap for graphene science and technology published February 25th, 2015

Quantum research past, present and future for discussion at AAAS February 16th, 2015

World’s first compact rotary 3D printer-cum-scanner unveiled at AAAS by NTU Singapore start-up: With production funded by crowdsourcing, the first unit will be delivered to the United States in March February 16th, 2015

Nanotechnology Electric Vehicle (EV) Market Analysis Report 2015: According to Radiant Insights, Inc February 13th, 2015

Discoveries

Democratizing synthetic biology: New method makes research cheaper, faster, and more accessible March 3rd, 2015

Pens filled with high-tech inks for do-it-yourself sensors March 3rd, 2015

Black phosphorus is new 'wonder material' for improving optical communication March 3rd, 2015

Heightened Efficiency in Purification of Wastewater Using Nanomembranes March 3rd, 2015

Materials/Metamaterials

Breakthrough in OLED technology March 2nd, 2015

Moving molecule writes letters: Caging of molecules allows investigation of equilibrium thermodynamics February 27th, 2015

Graphene shows potential as novel anti-cancer therapeutic strategy: University of Manchester scientists have used graphene to target and neutralise cancer stem cells while not harming other cells February 26th, 2015

Learning by eye: Silicon micro-funnels increase the efficiency of solar cells February 25th, 2015

Announcements

Democratizing synthetic biology: New method makes research cheaper, faster, and more accessible March 3rd, 2015

Pens filled with high-tech inks for do-it-yourself sensors March 3rd, 2015

Black phosphorus is new 'wonder material' for improving optical communication March 3rd, 2015

Heightened Efficiency in Purification of Wastewater Using Nanomembranes March 3rd, 2015

Environment

Pens filled with high-tech inks for do-it-yourself sensors March 3rd, 2015

Heightened Efficiency in Purification of Wastewater Using Nanomembranes March 3rd, 2015

Colon + septic tank = unique, at times stinky, study: Researchers use lab-scale human colon and septic tank to study impact of copper nanoparticles on the environment March 2nd, 2015

Simple, Cost-Efficient Method Used to Determine Toxicants Growing in Pistachio February 26th, 2015

Automotive/Transportation

Glass coating improves battery performance: To improve lithium-sulfur batteries, researchers added glass cage-like coating and graphene oxide March 2nd, 2015

Researchers turn unzipped nanotubes into possible alternative for platinum: Aerogel catalyst shows promise for fuel cells March 2nd, 2015

Scientific breakthrough in rechargeable batteries: Researchers from Singapore and Québec Team Up to Develop Next-Generation Materials to Power Electronic Devices and Electric Vehicles February 28th, 2015

In quest for better lithium-air batteries, chemists boost carbon's stability: Nanoparticle coatings improve stability, cyclability of '3DOm' carbon February 25th, 2015

NanoNews-Digest
The latest news from around the world, FREE




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More










ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project







© Copyright 1999-2015 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE