Lighting the way for the next generation of solar cells

Undergraduate Angela Ramos works in Professor Feimeng Zhou's lab.

Since she can remember, undergraduate chemistry student Angela Ramos has dreamt about being part of a “bigger change” for the earth and the environment.

“My family and I have always been into recycling and saving,” Ramos said. “And that was good—but it wasn’t enough.”

Well, the developing chemist and soon-to-be-Cal State L.A. graduate student, got her chance to participate in something “bigger” when she was accepted as a research fellow in the Center for Energy and Sustainability. Working alongside fellow students and professors with expertise in photochemistry, electrochemistry, fuel cell engineering and materials engineering, she has added to a collective body of research focused on improving solar cells.

“It’s helped me understand chemistry and concepts in renewable energy at a whole different level,” Ramos said of the center.

While photovoltaic cells, which create solar energy by converting sunlight into electrical power, are one of the “greenest” ways for producing power, the popularity and widespread implementation of the technology has been limited because of cost and efficiency concerns. Experts say that efficiency in solar photovoltaic cells currently ranges from only 10 percent to 25 percent.

“Solar energy harvesting, as practiced today, is still in its infancy,” said Mechanical Engineering Professor Adel Sharif. “Widespread harvesting of solar energy requires advances in materials science among other disciplines … and that will result in devices with higher efficiency and lower costs.”

To move the field forward, Cal State L.A.’s multidisciplinary research team—which also includes professors Feimeng Zhou, Radi Al-Jishi, David Blekhman and Matthias Selke—is testing new materials for solar cells and working to optimize everything from how solar cells absorb light and transfer energy, to the intensity of the electrical current produced. In particular, CSULA researchers are looking at these areas in relation to Quantum Dots, semi-conducting nano-crystals that absorb more light and have the potential to reduce costs and raise efficiency of solar cells—if issues in fabrication, stability, and energy transfer can be addressed.

With their results, the team hopes to construct a “new and improved” solar cell.

“The opportunity to bring scientists and engineers together is one of the nice things about working in a center like CEaS,” said Selke, who is an expert in the field of photochemistry, having studied for years how various compounds absorb light and participate in energy transfer—two important steps in the creation of solar energy.

“It’s very satisfying to see how your basic scientific research can lead to more interesting applications,” he added.