Louis Brus Wins 2005 American Chemical Society Materials Prize

It has been announced that Louis Brus, MRSEC Associate Director and Professor of Chemistry and Chemical Engineering, will be awarded the 2005 American Chemical Society (ACS) Chemistry of Materials Prize, sponsored by DuPont. The award recognizes research in establishing the field of semiconductor nanocrystals, which has applications that range from working as luminescent labels for studying biological systems to serving as effective components of medical diagnostic tools. Earlier in 2004, Brus was elected to the National Academy of Sciences, and he will be named the Samuel Latham Mitchill Professor of Chemistry.


 

Nick Turro and Colin Nuckolls Win 2004 Mayor Awards

William P. Schweitzer Professor of Chemistry Nicholas Turro was awarded the New York Mayor's Medal for Excellence in Physical Sciences. Colin Nuckolls, Associate Professor in the field of Organic Materials Chemistry, received the Mayor's Medal for Excellence in Science for a Young Investigator. Both are Columbia University MRSEC principal investigators.


 

Louis Brus is Elected to the National Academy of Sciences in 2004

Louis Brus, MRSEC Associate Director, Professor of Chemistry and Chemical Engineering and Thomas A. Edison Professor of Chemistry, has been elected to National Academy of Sciences. Brus is one of the founders of a new branch of solid state physics and chemistry: inorganic nanostructures. He has pioneered the study of physical, electronic and chemical properties of semiconductor nanocrystals as a function of their size. Brus was one of five Columbia University professors elected to the prestigious National Academy of Sciences. The announcement came during the Academy's 141 st annual meeting on April 20, 2004. A total of 72 new U.S. members were named, along with 18 foreign associates from 13 countries.


 

Nick Turro Wins the 2004 Pimentel Award in Chemical Education by the American Chemical Society

Nicholas Turro, William P. Schweitzer Professor of Chemistry, received the 2004 George C. Pimentel Award in Chemical Education by the American Chemical Society for his outstanding contributions to chemical education. He was presented with a certificate and $5,000 at the American Chemical Society's annual meeting in March, 2004. The symposium "Building Bridges to Understanding Chemistry through Innovation in Teaching and Education" was held in Turro's honor at this ACS Meeting.


 


MRSEC Congratulates Silverstein for Receiving the Mayor's Award

Dr. Samuel Silverstein, founder and director of the Summer Research Program(SRP) for High School Science Teachers, received the New York City Mayor's Award for Public Understanding of Science on October 8, 2003 for his work with the Summer Research Program. SRP has placed four teachers in the MRSEC Research for Teachers(RET) program each summer, and has co-sponsored them, making our MRSEC RET program a great success. We congratulate Dr. Silverstein for his wonderful work. (more information)

  
 


Columbia University MRSEC, IBM and The University of New Orleans Announce First 3-D Assembly of Magnetic and Semiconducting Nanoparticles

Yorktown Heights, NY, June 25, 2003 - Scientists from the Columbia University MRSEC, IBM and the University of New Orleans today announced a new, three-dimensional designer material assembled from two different types of particles only billionths of a meter across.

In the June 26 issue of the scientific journal Nature, the team describes the precision chemistry methods developed to tune the particles' sizes in increments of less than one nanometer and to tailor the experimental conditions so the particles would assemble themselves into repeating 3-D patterns.

Designing new materials with otherwise unattainable properties, sometimes referred to as "metamaterials," is one of the promises of nanotechnology. Two-dimensional patterns had previously been created from gold nanoparticles of different sizes and mixtures of gold and silver. Extending this concept to three dimensions with more diverse types of materials demonstrates the ability to bring more materials together than previously realized.

"What excites us the most is that this is a modular assembly method that will let us bring almost any materials together," said Christopher Murray, manager of nanoscale materials and devices at IBM Research. "We've demonstrated the ability to bring together complementary materials with an eye to creating materials with interesting custom properties."

Murray worked with Stephen O'Brien, assistant professor of applied physics and applied mathematics at Columbia University; Franz Redl, a postdoctoral researcher affiliated with both Columbia and IBM; and Kyung Sang Cho, a post-doctoral researcher affiliated with IBM and supported by the Advanced Materials Research Institute of the University of New Orleans. The work was supported in part by the National Science Foundation, the independent agency that supports basic research in all fields of science and engineering, through the Center for Nanostructured Materials at Columbia University and by the Defense Advanced Research Agency (DARPA) through programs on metamaterials and advanced thermoelectric materials.

The scientists chose the materials for the experiments specifically because of their dissimilar, yet complementary properties. Lead selenide is a semiconductor that has applications in infrared detectors and thermal imaging and can be tuned to be more sensitive to specific infrared wavelengths. The other material, magnetic iron oxide, is best known for its use in the coatings for certain magnetic recording media.

The combination of these nanoparticles may have novel magneto-optical properties as well as properties key to the realization of quantum computing. For example, it might be possible to modulate the material's optical properties by applying an external magnetic field.

"This was a demonstration of the ability to create such materials," O'Brien said. "Given the unique combination of these nanoscale materials, we're in uncharted territory with respect to the properties, which we will be working on in the future."

The first step was to create the nanoparticles. The particle sizes were calculated from the mathematical ideal of the structures they wanted to create. In addition to fine-tuning the sizes, the particles had to be very uniform, all within 5 percent of the target size. They settled on iron oxide particles 11 nanometers in diameter, which were created by Redl, and lead selenide particles 6 nanometers in diameter, created by Cho. There are approximately 60,000 atoms in one of the iron oxide nanoparticles and approximately 3,000 atoms in the lead selenide particles.

Next, Redl assembled the nanoparticles - or more to the point, had the particles assemble themselves-into three different repeating 3-D patterns by tailoring the experimental conditions. Forming these so-called "crystal structures," as opposed to random mixtures of nanoparticles, is essential for the composite material to exhibit consistent, predictable behaviors. Various other materials are known to assemble spontaneously into these structures of close-packed particles, but none has been made of two components in three dimensions and at the length scales reported in the Nature paper.

"The precise and energy-efficient self-assembly of matter into material structures with properties that cannot be achieved otherwise is an important goal for nanotechnology," said Mihail Roco, NSF senior advisor for nanotechnology and chair of the National Science and Technology Council's Subcommittee on Nanoscale Science and Engineering. "This is just one way that nanotechnology will help foster 'the next industrial revolution.'"

For more details see related sites at Columbia University, NSF, and IBM .

To view a QuickTime Movie of the formation of the Bimodal Superlattice, please click here

  

TEM (left) of ordered array of 11 nm diameter maghemite (gamma-Fe2O3, blue in schematic) and 6 nm diameter lead selenide (PbSe, red) nanocrystals.


 

Nick Turro Wins Major Columbia Teaching Award

NIcholas Turro was awarded a Presidential Award for Excellence in Teaching at Columbia University's 249th Commencemnt on May 21, 2003. This prestigious award was awarded to only five faculty in the entire university. George Flynn is a previous winner of this award. For more details see Columbia University Commencement.


 

Siu-Wai Chan named a 2003 Guggenheim Fellow

Siu-Wai Chan of the Columbia MRSEC and the Materials Science and Engineering Program in the Department of Applied Physics and Applied Mathematics has been named a 2003 Guggenheim Fellow to support her research in new methods of preparing grain-boundary junctions of high temperature superconductors. This year there are five new Guggenheim Fellows at Columbia. Within the Columbia MRSEC, Prof. Chan investigates the synthesis and properties of cerium oxide nanocrystals and leads the high school visitation program. For more details see Columbia 2003 Guggenheim Fellows.