DeKalb, Illinois — Researchers from Northern Illinois University and the U.S. Department of Energy (DOE)’s National Renewable Energy Laboratory (NREL) in Golden, Colorado report a potential breakthrough that may help Accelerate the commercialization of promising perovskite solar cells (PSC) for solar panels.

A layer of lead-absorbing material is scraped onto a standard solar ethylene vinyl acetate (EVA) film. Image credit: Li Xun, Northern Illinois University

In a brief exchange with Nature Sustainability magazine on October 28, the scientists described the development of a cost-effective transparent tape-like film that can be applied to PSC and capture 99.9% of the leaked lead when the solar cell is damaged.

According to the research team, this industrial-grade film will help alleviate health and safety issues without affecting the performance or operation of perovskite solar cells. The test for the lead-absorbing film involves immersing the damaged battery in water.

"Our practical approach reduces potential lead leakage to a level that is safer than drinking water standards," said Xu Tao, a professor of chemistry at NIU, who co-led the research with Zhu Kai of the NREL National Renewable Energy Laboratory.

Professor Tao Xu and student Li Xun of Northern Illinois University. Image source: Northern Illinois University

“We can easily apply our lead-absorbing materials to the ready-made thin films currently used to encapsulate silicon-based solar cells at the end of production, so it will not disrupt the existing manufacturing process of PSC,” Xu added. "At the end of PSC production, these films will be laminated to solar cells."

As a new type of solar cell, PSC is considered a rising star in the solar field due to its high power conversion efficiency (over 25.5%) and low manufacturing cost. However, PSC has not yet been commercialized on a large scale because key challenges still exist, including potential lead toxicity issues.

A small amount of water-soluble lead is still an important part of the high-efficiency PSC light-absorbing layer, and the PSC must be able to withstand harsh weather to achieve commercial viability. Large amounts of lead leakage from damaged batteries can cause health and safety issues.

To solve these problems, scotch tape uses a lead absorber made of a standard solar ethylene vinyl acetate (EVA) film and a pre-laminated layer of lead absorbing material. The tape can be attached to both sides of the manufactured PSC, just like the standard packaging process used in silicon-based solar cells.

A perovskite solar cell encapsulated with a transparent lead-absorbing film. Image credit: Li Xun, Northern Illinois University

In a test used to evaluate the durability of the new technology, the scientists exposed the film-encapsulated PSC to outdoor roof conditions for three months. Then use a razor blade and a hammer to damage the solar cells, and then submerge them in water for 7 days. The lead absorption tape shows a lead storage efficiency of more than 99.9%.

"Perovskite solar cells have high hopes for a more sustainable future," Xu said. "This work provides a convenient and industry-friendly method to reduce potential lead leakage from lead-containing PSCs and promote the future commercialization of perovskite-based photovoltaic technology."

The research was supported by the Office of Energy Efficiency and Renewable Energy under the Office of Energy Technology. In addition to Xu and Zhu, the authors of the Nature Sustainability newsletter are students of Li Xun and Wang Jianxin of the NIU Ph.D. NREL Center for Chemistry and Nanoscience, as well as postdoctoral researchers Zhang Fei and Tong Jinhui.

NREL is leading the commercialization of this new lead absorption technology, but interested companies can also contact NIU Innovation Director Luke Sebby and Assistant Director of Technology Transfer Mark Hankins.

Northern Illinois University is a student-centered, nationally recognized public research university. Its expertise benefits the region and spreads across all fields around the world, including science, humanities, arts, business, engineering, education, health, and law. Through its main campus in DeKalb, Illinois, and student and professional education centers in Chicago, Naperville, Oregon, and Rockford, NIU offers more than 100 fields of study while serving a diverse international student body.

DeKalb, Illinois - Researchers from Northern Illinois University and the U.S. Department of Energy (DOE) National Renewable Energy...

An international team of scientists including NIU researchers has developed a pioneering route...

The students hidden in the campus laboratory are quietly designing small molecules to...

© 2017 Northern Illinois University Board of Trustees. all rights reserved.