UCLA scientists Develop New Transparent Solar Cells Generating Electricity

UCLA researchers have developed a new and innovative transparent solar cell that is an advance towards giving windows in homes and other buildings the ability to generate electricity while still allowing people to see outside.  

The new study that was published in the Journal ACS Nano, is described as a new polymer solar cell (PSC) the that produces energy by absorbing mainly infrared light, and not the visible light making the cells nearly 70 percent transparent to the human to the human eye.

This unique and interesting device is designed from a photoactive plastic that converts infrared light into an electrical current was designed by the team of UCLA researchers from the California NanoSystems Institute,  the UCLA Henry Samueli School of Engineering and Applied Science and UCLA's Department of Chemistry and Biochemistry.

They have demonstrated high-performance, solution-processed, visibly transparent polymer solar cells through the incorporation of near-infrared light-sensitive polymer and using silver nanowire composite films as the top transparent electrode. The near-infrared photoactive polymer absorbs more near-infrared light but is less sensitive to visible light, balancing solar cell performance and transparency in the visible wavelength region.

"These results open the potential for visibly transparent polymer solar cells as add-on components of portable electronics, smart windows and building-integrated photovoltaic's and in other applications," said study leader Yang Yang, a UCLA professor of materials science and engineering, who also is director of the Nano Renewable Energy Center at California NanoSystems Institute (CNSI). Yang added that there has been intense world-wide interest in so-called polymer solar cells. "Our new PSCs are made from plastic-like materials and are lightweight and flexible," he said. "More importantly, they can be produced in high volume at low cost."

Polymer photovoltaic cells have attracted great attention due to their advantages over competing solar-cell technologies. Scientists have also been intensely investigating PSCs for their potential in making advances for broader applications.

Another plus point in for this design is that it is polymer based and made in solution. Though the 4 percent efficiency is not particularly great, these other factors give this design great potential, and that efficiency can only increase as the UCLA researchers and others continue their work.

"We are excited by this new invention on transparent solar cells, which applied our recent advances in transparent conducting windows to fabricate these devices," said Paul S.Weiss, CNSI director and Fred Kavli Chair in NanoSystems Sciences.