Tapping solar’s full potential

Solar cells may be a little closer to full realization of their potential, thanks to the creation of large sheets of nanotextured silicon microcell arrays. The discovery promises to make solar cells lightweight, bendable, more efficient and easily mass-produced.

Converting sunshine into electricity is not a difficult process, although the lack of a national solar cell network reveals that much of the difficulty lies in doing so efficiently and on a large scale.

A printed solar cell is shown. Researchers have created large sheets of nanotextured silicon microcell arrays that could make solar cells easier to mass-produce. Photo courtesy of University of Central Florida.

But a team from the University of Illinois at Urbana-Champaign (UIUC) and the University of Central Florida (UCF) in Orlando may be one step closer. The group used a light-trapping scheme based on a nanoimprinting technique in which a polymeric stamp mechanically embosses a nanoscale pattern onto the solar cell without additional complex lithographic steps. This approach provides the flexibility that investigators have been searching for, making the design ideal for mass manufacturing, said UCF assistant professor Debashis Chanda, lead researcher of the study.

Previously, scientists had suggested designs that showed higher rates of sun-light absorption, but how efficiently that sunlight was converted into electrical energy was unclear, Chanda said. This study demonstrates that the researchers’ light-trapping scheme offers higher electrical efficiency in a lightweight, flexible module.

This technology could someday lead to solar-powered homes fueled by cells that are reliable and provide stored energy for hours without interruption, the team said.

Chanda, who joined UCF in the fall of 2012 from UIUC, has joint appointments at the Nanoscience Technology Center and the College of Optics and Photonics (CREOL). He has published multiple articles on light-matter interactions and metamaterials. For some of his pioneering works, Chanda received a Department of Energy solar innovation award and a Natural Sciences and Engineering Research Council award, among others. He also earned a National Science Foundation Summer Institute Fellowship last year.

The study’s findings are featured in Advanced Energy Materials (doi: 10.1002/aenm.201370046).