Faculty Profile: Chemistry Professor C. J. Zhong

NSF career award supports nanoworld research efforts

C. J. Zhong, a recent winner of a $465,000 career award from the National Science Foundation, is exploring new research opportunities in his work, which involves fundamental research as well as the development of practical applications.

A $465,000 career award from the National Science Foundation is the latest in large-scale support for a Binghamton University chemist who is exploring new research opportunities at the scale of the infinitesimal.
C. J. Zhong, who joined the faculty at Binghamton in 1998, is committed to advancing our understanding of the nanoworld, where structures tens of thousands of times smaller than a human hair behave in ways scientists are only now learning to predict. His work has high-stakes implications in fields as diverse as chemical and biological sensing, information storage and catalysis.

Catalysis, or the acceleration of chemical reactions by materials that are chemically unchanged at the end of the reaction, saves money by making reactions possible at lower temperatures, with smaller quantities of materials or by generally reducing the energy requirements. It is key to the development of fuel cell vehicles and is involved in more than 80 percent of all chemical processing. The production of petroleum products is entirely reliant on it.
But the rules of engagement for catalysis in the nanorealm are very different than they are at larger scales. In fact, across the board, sensory, magnetic, electronic and catalytic properties of nanoscale particles have little or no precedent.

"When you are working at nanoscale, it's not just that things get smaller, it's that there are a whole different range of possible outcomes," Zhong said. "Nanoscale right now is an entirely new world."

Even the most familiar of compounds behave very differently at nanoscale -- or billionth-of-a-meter -- proportions. As a prime example, Zhong points to the metal gold, which has long served as a preferred model for research because it is not easily oxidized. Many other metals tend to break downeasily and degrade during experimentation. Gold, which in bulk form appears yellow, melts at over 1,000¾C, and in the past has not generally been viewed as much of a catalyst. "That's why we use it for jewelry," Zhong joked.

Gold nanoparticles, however, are a different story. They melt when heated to only a few hundred degrees C and are proving able catalysts in a broad range of reactions, where they more easily and less expensively lower barriers to important reactions than do more traditional competitors, such as platinum. At nanoscale, even the yellow color from which gold draws its name changes. Gold nanoparticles can appear as red, blue or a wide variety of other colors, depending on their size and spacing from each other, Zhong noted. This characteristic, first capitalized on by ancient artisans who used tiny flakes of gold to colorfully decorate everything from jewelry to vases, today offers great promise in the field of biological sensors, Zhong said.

"Current technology is micron technology and most students are comfortable with that. But 10 years down the road, everything will be nanotechnology, and we have to start preparing them to live and work in that world as well." -- C. J. Zhong

Since the visible color of gold nanoparticles changes depending on their spacing, if specific DNA strains can be made to hook up with nanoparticles of gold and thereby to change the spacing of the gold particles, the visible color of the gold particles will change. That makes it possible to develop gold-particle biosensors that are essentially the nanoparticle equivalent of litmus paper, providing a quick, visible signal to indicate something important about the environment to which they are exposed.

Similarly, by making use of magnetic and electronic properties of specific nanoparticles, which can also be very different from those associated with larger particles of the same substance, important new information storage applications will likely be developed, he said.

Because of the sweeping implications of his work, Zhong enjoys more than $600,000 in funding from sponsors in addition to his NSF career award. Those sponsors include the NSF by means of other awards, the American Chemical Society, the World Gold Council and Honda, for which he conducts research that could prove critical to the development of fuel cell vehicles.

As part of his NSF career award research plan, Zhong expects to develop novel mediator-template pathways as a general strategy for assembling nanoparticles, making it possible to better control the size, shape and interspatial properties of assembled nanoparticles. He also hopes to develop new design parameters, an approach that will allow for the electrical and binding properties of nanoparticles to be tuned for such specific applications as chemical sensors and biosensors.

But Zhong's research isn't the only thing that should be significantly advanced by the NSF career award, which is expected to span the next five years. The award also places strong emphasis on curriculum development. Zhong intends to develop new graduate and undergraduate course modules centered on "nanoscale chemistry," he said. The educational component will also involve hands-on interdisciplinary activities and outreach to area high schools.

" Current technology is micron technology and most students are comfortable with that," he said. "But 10 years down the road, everything will be nanotechnology, and we have to start preparing them to live and work in that world as well. This small stuff is going to be big for a very long time."
-- Susan E. Barker