The US Air Force Office of Scientific Research has been funding a flurry of gold nanoparticle projects at academic research centers around the country, and one of the future beneficiaries of all this activity could be the US solar industry.
In the latest development, an AFOSR-supported research team at the University of Florida has fine-tuned the pathway by which light can be used to synthesize precisely structured gold nanocrystals.
The use of light to grow nanoscale crystals is old hat, relatively speaking. The process, called plasmon-driven synthesis, has been used to form precisely engineered nanoparticles of silver. That’s well and good but silver has a limited range of applications, especially when it comes to medical purposes.
Human systems tolerate gold very well, but until now researchers have not been able to control plasmon-driven synthesis precisely enough to yield consistent results.
The UF team came up with a solution that involves integrating a common water-soluble food additive called polyvinylpyrrolidone into the process. For those of you familiar with the stuff ‘s crystal-blocking traits that strategy might sound counter intuitive. However, the team found that when it sticks to the perimeter of emerging gold nanoprisms, it acts as a “photochemical relay” that precisely engineers the growth pattern.
You can get more details from the journal Nature Communications under the title, “Polyvinylpyrrolidone-induced anisotropic growth of gold nanoprisms in plasmon-driven synthesis.”
The team also discovered an energy efficiency bonus. In addition to delivering precise, high-yield results, the new plasmon-driven process can operate at low power, using light in the visible range.
Solar Power Hearts Gold
Medical applications seem to be generating the most excitement around the new research, and the team also anticipates that the new process could be combined with solar cells to perform chemical synthesis.
A research team in Australia, for example, has applied gold and silver nanoparticles to off-the-shelf thin-film solar cells, to achieve an increase in the range of wavelength of absorbed sunlight.
The emergence of an efficient, relatively low-cost method for fabricating gold nanocrystals could also impact other research efforts that integrate plasmonics and solar energy.
Deploying gold nanoparticles to enhance solar-powered steam production is another solar-related area of research. Other cleantech applications include enhanced bioluminescence and stretchable electronics.
US Air Force Hearts Gold
The new UF research (which was also partly funded by the National Science Foundation), is just one example of the AFOSR’s interest in gold nanoparticle research.
AFOSR also has a research team at Oregon State University working on the manufacture of uniform gold nanoparticles, and an AFOSR-supported team at Carnegie Mellon University has been synthesizing gold nanoparticles and mapping their structure “atom by atom.”
Source: Clean Techinica