ISU Magazine

Volume 40 | Number 2 | Spring/Summer 2010

Researchers Joshua Pak and René Rodriguez

Researchers Joshua Pak and René Rodriguez

Photo by ISU Photographic Services/Susan Duncan

Tiny Particles Help Make Big Advances

Spring 2010 Issue | By Andrew Taylor

ISU researchers seek clues on how tiny nanoparticles can harness sun’s energy

Idaho State University chemistry professors Joshua Pak and René Rodriguez are using some of the tiniest pieces of matter to attempt to better harness the energy from the largest energy source in our solar system — the sun.

Pak and Rodriquez, who are working with the Idaho National Laboratory’s Robert Fox, are using particles so small it would take a million of them lined up next to each other to reach across the circumference of the period at the end of this sentence. The ISU researchers have helped create a process for making uniformed-sized particles smaller than 20 nanometers.

For their efforts, these researchers along with the INL’s Fox, were nationally recognized last July with an R&D Magazine R&D 100 Award for one of the top 100 research and development discoveries in 2009. They were also honored last September with an Idaho Innovation Awards “Early-Stage Innovation of the Year” for their work with precision nanoparticles. These awards were publicized widely on the Internet and in scientific media outlets.

One of the primary chemicals Pak, Rodriguez and Fox are studying is copper indium sulfide.

“It is known to be a good solar-cell material and could be used to absorb solar energy into electricity,” Pak said.

Particles of this substance at sizes less than 20 nanometers can have properties they don’t have at larger sizes due to the “quantum effect.” Simply put, molecules and atoms of copper indium sulfide, or a piece of wood for that matter, essentially have the same characteristics as they grow regressively smaller until they reach the incredibly small sizes the ISU and INL researchers are able to create. At that point, at 100 nanometers and smaller, they can take on different qualities.

In sizes of less than 20 nanometers copper indium sulfide is more efficient at storing solar energy.

“One of our main goals with nanotechnology is to create versions of the chemical that are better at storing energy and could be used to create more efficient solar cells (for making solar energy) at a cheaper cost,” Pak said.

The revolutionary technology these researchers created efficiently produces nanoparticles in uniform and precise sizes. The precision nanoparticle technology has been licensed to Precision Nanoparticles, Inc., of Seattle.

Uniformity is very important because a chemical such as copper indium sulfite will have different, and perhaps more optimum properties at, for example, 15 nanoparticles, than it would at 10 or 30, or at a mixture of sizes.

“For use in energy systems, we have to know how to make these particles and have to know how to make the right composition, right size at the right phase. We’ve achieved the ability to control the sizes very well,” Pak said.

One of the next major challenges facing the scientists is to develop a way that billions of nanoparticles can be created and then applied as a thin film to solar cells to collect the sun’s energy. The ISU researchers are attempting to create a nanoparticle composite that could be applied to crystal silicon solar cells to harness the sun’s energy.

“It is difficult to put these nanoparticle composites in a solar cell and have them work,” Rodriguez said. “A lot of smart people in the world are trying to do similar things that we are, trying to achieve this.”

Pak has faith that scientists will meet this challenge.

“I believe within 10 years scientists will develop processes to use nanoparticles to create energy in an efficient, cheaper and environmentally friendly manner,” Pak said.

Seed money for Rodriguez and Pak’s research was made possible partly through support from the DOE and partly from a Laboratory Directed Research Development Grant from the Center for Advanced Energy Studies in Idaho Falls. CAES is a public/private partnership comprised of the three Idaho public universities, private industry and the Idaho National Laboratory.