Nanotechnology Now

Our NanoNews Digest Sponsors





Heifer International

Wikipedia Affiliate Button


android tablet pc

Home > Press > Next scientific fashion could be designer nanocrystals



Prof. David Mazziotti (above) and colleagues Dmitri Talapin and Greg Engel are attempting to formulate the basic principles needed to improve the efficiency and information transfer of electrons in nanocrystals. “That kind of thing you can play into many applications,” said Mazziotii.
Photo by Lloyd DeGrane
Prof. David Mazziotti (above) and colleagues Dmitri Talapin and Greg Engel are attempting to formulate the basic principles needed to improve the efficiency and information transfer of electrons in nanocrystals. “That kind of thing you can play into many applications,” said Mazziotii.

Photo by Lloyd DeGrane

Abstract:
Three University of Chicago chemistry professors hope that their separate research trajectories will converge to create a new way of assembling what they call "designer atoms" into materials with a broad array of potentially useful properties and functions.

Next scientific fashion could be designer nanocrystals

Chicago, IL | Posted on December 11th, 2012

These "designer atoms" would be nanocrystals—crystalline arrays of atoms intended to be manipulated in ways that go beyond standard uses of atoms in the periodic table. Such arrays would be suited to address challenges in solar energy, quantum computing and functional materials.

The partners in the project are Prof. David Mazziotti, and Associate Professors Greg Engel and Dmitri Talapin. All three have made key advances that are critical for moving the project forward. Now, with $1 million in funding from the W. M. Keck Foundation, they can build on their separate advances in a concerted way toward a new goal.

"If you look at the history of science, a major development starts with people of different backgrounds talking to each other and learning from each other and doing something really revolutionary rather than incremental," Talapin said.

Developments in Talapin's laboratory form the core of the project. A synthetic inorganic chemist, he specializes in creating precisely engineered nanocrystals with well-defined characteristics.

Nanocrystals consist of hundreds or thousands of atoms. This is small enough that new quantum phenomena begin to emerge, but large enough to provide convenient "modules" for the design of new materials. "It's an interesting combination in that you build materials not from individual atoms, but from the units that resemble atoms in many ways but also behave as a metal, semiconductor or magnet. It's a bit crazy," Talapin said.

The potential of the new arrangements may exceed that of existing elements. Chemists cannot tune the properties of hydrogen or helium, for example, but they can tune the properties of nanocrystals.

"You build chemistry from atoms, and quantum mechanics provides principles for doing that," said Mazziotti, referring to the laws of physics that dominate the world at ultra-small scales. "In the same way, we envision tremendous opportunities in terms of taking nanocrystalline arrays and nanocrystals as the building blocks for new structures where we assemble them into strongly correlated systems."
Nanocrystalline building blocks

The essence of strong correlation, of chemical bonds, of chemistry generally, is the connections between particles and how properties of these particles change as they bind to one another, Engel noted. "It's about new emerging properties coming from strong mixing between the electronic states of particles, the same way two atoms come together to make a molecule," he said.

Hydrogen and oxygen gases have very different properties. Yet when two hydrogen atoms share electrons with an oxygen atom, they form water. The UChicago trio's ambition is to extend this framework from the level of individual atoms to the level of small, functional objects, such as metal or magnetic semiconductors.

The key to their project is controlling the degree of correlation between electrons on different nanocrystals. In 2009, Talapin and his collaborators developed a way to control the motions of electrons as they move from one nanocrystal to the next. Their "electronic glue" enables semiconductor nanocrystals to efficiently transfer their electric charges to one another, an important step in the synthesis of new materials.

"That glue is provided by a special tuning of the behavior of the electrons," Mazziotti said. "You want the electrons to have their motions correlated in a special way to allow the efficient transfer of that energy from one nanocrystal to the other."

Achieving greater control of correlated electrons—those whose motions are linked to each other—on different nanocrystals is the key to success in the Keck project.

"If we can enhance that, then we can essentially develop a whole palette of new materials that essentially derives from using the nanocrystals as building blocks and strong correlation as a way of tuning, essentially, the degree to which or how they talk to each other," Mazziotti said. "We want really efficient transfer of energy and information between the different units. Previously in the area of nanocrystalline arrays, the nanocrystals only communicated with each other very weakly."
Developing a new palette

Mazziotti and Engel bring theoretical and spectroscopic advances, respectively, to the collaboration. Mazziotti's advance provides an alternative to traditional approaches to computing strongly correlated electrons in molecules, which scale exponentially with the number of electrons. He has solved a longstanding problem that enables calculations using just two of a molecule's electrons, which dramatically decreases the computational cost.

His studies of firefly bioluminescence and other phenomena have shown that as molecular systems grow larger, strong correlations between electrons grow more powerful and open new possibilities for emergent behavior. In the context of a semiconducting material such as silicon, emergent behavior is how individual nanoparticles effectively lose their identity, giving rise to collective properties in new materials.

"As the size of a molecular system increases, we see the emergence of new physics behavior and the importance of strong correlation of electrons," Mazziotti said. "The importance of strong correlation increases dramatically with system size."

The advance in Engel's research group was the development of a technique called GRadient-Assisted Photon Echo (GRAPE) spectroscopy, which borrows ideas from magnetic resonance imaging but is used for spectroscopy rather than medical imaging. Engel already has used GRAPE to observe the correlated motion and coupling between chromophores, which are light-absorbing molecules. Now he will apply the technique to nanocrystals.

"This, for the first time, will let us really see the direct nature of the electronic coupling that's at the heart of this idea of new bonding concepts in designer atoms," Engel said. "We'll be able to provide the experimental evidence that will combine the theory that David is developing with the new structures that Dmitri is building."

Based in Los Angeles, the W. M. Keck Foundation was established in 1954 by the late W. M. Keck, founder of the Superior Oil Company. The foundation's grant making is focused primarily on pioneering efforts in medical research, science and engineering. The foundation also maintains a program to support undergraduate science and humanities education and a Southern California Grant Program that provides support in health care, civic and community services, education and the arts, with a special emphasis on children.

By Steve Koppes

####

For more information, please click here

Contacts:
Steve Koppes
News Officer for Physical Sciences
News Office, University Communications

(773) 702-8366

Copyright © University of Chicago

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

Imaging

New imaging agent provides better picture of the gut July 30th, 2014

FEI Unveils New Solutions for Faster Time-to-Analysis in Metals Research July 30th, 2014

News and information

East China University of Science and Technology Purchases Nanonex Advanced Nanoimprint Tool NX-B200 July 30th, 2014

Watching Schrödinger's cat die (or come to life): Steering quantum evolution & using probes to conduct continuous error correction in quantum computers July 30th, 2014

From Narrow to Broad July 30th, 2014

FLAG-ERA and TNT2014 join efforts: Graphene Networking at its higher level in Barcelona: Encourage the participation in a joint transnational call July 30th, 2014

Physics

Watching Schrödinger's cat die (or come to life): Steering quantum evolution & using probes to conduct continuous error correction in quantum computers July 30th, 2014

Flexible Metamaterial Absorbers July 29th, 2014

Chemistry

Nature inspires a greener way to make colorful plastics July 30th, 2014

Tough foam from tiny sheets: Rice University lab uses atom-thick materials to make ultralight foam July 29th, 2014

Discoveries

New imaging agent provides better picture of the gut July 30th, 2014

Watching Schrödinger's cat die (or come to life): Steering quantum evolution & using probes to conduct continuous error correction in quantum computers July 30th, 2014

From Narrow to Broad July 30th, 2014

A new way to make microstructured surfaces: Method can produce strong, lightweight materials with specific surface properties July 29th, 2014

Materials/Metamaterials

From Narrow to Broad July 30th, 2014

Nature inspires a greener way to make colorful plastics July 30th, 2014

Tough foam from tiny sheets: Rice University lab uses atom-thick materials to make ultralight foam July 29th, 2014

A new way to make microstructured surfaces: Method can produce strong, lightweight materials with specific surface properties July 29th, 2014

Announcements

University of Manchester selects Anasys AFM-IR for coatings and corrosion research July 30th, 2014

Nature inspires a greener way to make colorful plastics July 30th, 2014

Analytical solutions from Malvern Instruments support University of Wisconsin-Milwaukee researchers in understanding environmental effects of nanomaterials July 30th, 2014

FEI Unveils New Solutions for Faster Time-to-Analysis in Metals Research July 30th, 2014

Tools

New imaging agent provides better picture of the gut July 30th, 2014

Nanometrics Reports Second Quarter 2014 Financial Results July 30th, 2014

New Objective Focusing Nanopositioner from nPoint July 30th, 2014

University of Manchester selects Anasys AFM-IR for coatings and corrosion research July 30th, 2014

Energy

From Narrow to Broad July 30th, 2014

Oregon chemists eye improved thin films with metal substitution: Solution-based inorganic process could drive more efficient electronics and solar devices July 21st, 2014

Steam from the sun: New spongelike structure converts solar energy into steam July 21st, 2014

3-D nanostructure could benefit nanoelectronics, gas storage: Rice U. researchers predict functional advantages of 3-D boron nitride July 15th, 2014

Grants/Awards/Scholarships/Gifts/Contests/Honors/Records

New imaging agent provides better picture of the gut July 25th, 2014

Hysitron is Awarded TWO R&D 100 Awards for Highly Innovative Technology Developments in the Areas of Extreme Environments and Biological Mechanical Property Testing July 23rd, 2014

Researchers create vaccine for dust-mite allergies Main Page Content: Vaccine reduced lung inflammation to allergens in lab and animal tests July 22nd, 2014

EPFL Research on the use of AFM based nanoscale IR spectroscopy for the study of single amyloid molecules wins poster competition at Swiss Physics Society meeting July 22nd, 2014

Solar/Photovoltaic

From Narrow to Broad July 30th, 2014

Steam from the sun: New spongelike structure converts solar energy into steam July 21st, 2014

Making dreams come true: Making graphene from plastic? July 2nd, 2014

Shrinky Dinks close the gap for nanowires July 1st, 2014

Quantum nanoscience

Measuring the Smallest Magnets July 28th, 2014

Physicists Use Computer Models to Reveal Quantum Effects in Biological Oxygen Transport: The team solved a long-standing question by explaining why oxygen – and not deadly carbon monoxide – preferably binds to the proteins that transport it around the body. July 17th, 2014

Bending the rules: A UCSB postdoctoral scholar in physics discovers a counterintuitive phenomenon: the coexistence of superconductivity with dissipation June 29th, 2014

Singapore Researchers Use FEI Titan S/TEM to Link Plasmonics with Molecular Electronics: As described in the March 28 issue of Science, researchers discover quantum plasmonic tunneling – a phenomenon that may eventually lead to new, ultra-fast electrical circuits June 24th, 2014

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 1999-2014 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE