Researchers at the University of Maryland are reporting new advances in nanoscience that will enable the creation of new nanostructures that could greatly accelerate the generation of clean energy.
The study found an entirely new strategy for synthesizing hybrid nanostructures – extremely small devices such as those found on a computer chip. This strategy uses a nanoparticle to join other nanoparticles into the nanostructures in a way that would be difficult if not impossible to make with the conventional method, which relies on crystalline growths.
Using nanoparticles to join other nanoparticles doesn’t have the drawbacks of nanostructures that are assembled with crystals. Those drawbacks include a limit on what materials can be joined, as well as constraints on the size, shape and symmetry of conventional nanostructures.
The leader of the Maryland team, Min Ouyang, an associate professor of physics, says the method enables the creation of more complex and materially varied nanostructures whose shapes are easier to customize to their function. He likens this feature to the body’s ability to create specific protein molecules, “each with a specific function determined by its specific composition and shape.”
“Such a synthesis method is the dream of many scientists in our field and we expect researchers now will use our approach to fabricate a full class of new nanoscale hybrid structures,” Ouyang said.
One key application of the new nanostructures may lead to what’s called a “light-generated nanoparticle effect,” which was first used thousands of years ago by ancient Roman artisans to create glass that changes color in different kinds of light. This effect, known as plasmon resonance, generates high-energy electrons.
Ouyang says that under plasmon resonance, light generates “collective oscillation” of low-energy electrons, which are stored up, then are converted into high-energy carriers called “hot electrons” to generate clean electrical power.
This process is similar to photosynthesis, in which the chlorophyll in plants uses solar energy to convert carbon dioxide, water and other matter into food. It has recently been the subject of much scientific study with the aim of generating clean energy.
The research, published in the Sept. 2 issue of Nature Communications, has drawn the praise of several scientists who weren’t involved in Ouyang’s research. One is Professor Martin Moskovits of the University of California-Santa Barbara.
Moskovits noted that the nanostructures created by Ouyang’s team, which include “the novel feature of a silver-gold particle that super efficiently harvests light, bring us a giant step nearer the so-far elusive goal of artificial photosynthesis: using sunlight to transform water and carbon dioxide into fuels and valuable chemicals.”
Using sunlight to split water molecules into hydrogen and oxygen to produce hydrogen fuel has for years been a goal in clean energy research, but until Ouyang’s team began work on the problem, no one has figured out how to do it.
By Andy Tully of Oilprice.com
Andy Tully is a veteran news reporter who is now the news editor for Oilprice.com