Researchers improve safety of lead-based perovskite solar cells

February 25, 2020

Researchers at the National Renewable Energy Laboratory (NREL) and Northern Illinois University (NIU) have developed a technique to sequester the lead used to make perovskite solar cells, a highly efficient emerging photovoltaic technology.

The light-absorbing layer in a perovskite solar cell contains a minute amount of lead. The presence of this toxic material in the developing technology could turn some consumers away when perovskite solar cells become commercially available, said Kai Zhu, a senior scientist in the Chemistry and Nanoscience Center at NREL.

Zhu and other researchers at NREL and NIU outlined their solution in a paper newly published in Nature, titled "On-Device Lead Sequestration for Perovskite Solar Cells."

"This is a big step in the correct direction," Zhu said. His co-authors are Fei Zhang and Joseph Berry of NREL, Haiying He of Valparaiso University, and Xun Li and Tao Xu from NIU. Xu served as the lead researcher from NIU.

"Lead toxicity has been one of the most vexing, last-mile challenges facing perovskite solar cells," Xu said. "Our on-device lead-sequestration method renders a 'safety belt' for this fascinating photovoltaic technology."

A lead-based perovskite solar cell's highest efficiency--its ability to turn sunlight into electricity--runs close to 25%. Without the lead, that efficiency is cut in half.

Silicon solar panels, the industry's dominant technology, contain lead solder, but that lead is not water soluble. The lead used in perovskites can be dissolved in water. While existing analyses show this is not a major concern, the researchers developed a method to ensure the lead is sequestered should a cell become damaged. They coated the front and back of a perovskite solar cell with two different lead-absorbing films. Then, they damaged the two sides of the cell--slashing one with a knife and smashing the other with a hammer.

The researchers then immersed the damaged cells in water of various types, including pure water, acid water, and even flowing water to simulate heavy rain. They found that these lead-absorbing films can prevent more than 96% of lead from leaking into the water from the damaged cells.

The addition of the lead-absorbing layers did not affect the performance of the solar cell, the researchers found.
-end-
The research was funded by the National Science Foundation and the U.S. Department of Energy's Solar Energy Technologies Office.

NREL is the U.S. Department of Energy's primary national laboratory for renewable energy and energy efficiency research and development. NREL is operated for the Energy Department by The Alliance for Sustainable Energy, LLC.

DOE/National Renewable Energy Laboratory

Related Solar Cell Articles from Brightsurf:

Theoretically, two layers are better than one for solar-cell efficiency
Solar cells have come a long way, but inexpensive, thin film solar cells are still far behind more expensive, crystalline solar cells in efficiency.

USTC made breakthrough in the Sb2(S,Se)3 solar cell efficiency
USTC developed a hydrothermal deposition method for the synthesis of antimony selenosulfide for solar cell applications.

Oxygen breathes new life into solar cell research
Scientists in Australia and the United States have been able to 'upconvert' low energy light into high energy light, which can be captured by solar cells, in a new way, with oxygen the surprise secret ingredient.

Merging solar cell and liquid battery produces long-lasting solar storage
Combining liquid chemical battery technology with perovskite solar cells has led to a new record in solar energy conversion within a single device.

Merging solar cell and liquid battery produces efficient, long-lasting solar storage
Chemists at the University of Wisconsin-Madison and their collaborators have created a highly efficient and long-lasting solar flow battery, a way to generate, store and redeliver renewable electricity from the sun in one device.

Windows will soon generate electricity, following solar cell breakthrough
Semi-transparent solar cells that can be incorporated into window glass are a 'game-changer' that could transform architecture, urban planning and electricity generation, Australian scientists say in a paper in Nano Energy.

Ultrathin organic solar cell is both efficient and durable
Scientists have succeeded in creating an ultrathin organic solar cell that is both highly efficient and durable.

Layered solar cell technology boosts efficiency, affordability
Researchers from CU Boulder have created a low-cost solar cell with one of the highest power-conversion efficiencies to date, by layering cells and using a unique combination of elements.

Anti-solar cells: A photovoltaic cell that works at night
What if solar cells worked at night? That's no joke, according to Jeremy Munday, professor in the Department of Electrical and Computer Engineering at UC Davis.

Promising discovery could lead to a better, cheaper solar cell
McGill University researchers have gained tantalizing new insights into the properties of perovskites, one of the world's most promising materials in the quest to produce a more efficient, robust and cheaper solar cell.

Read More: Solar Cell News and Solar Cell Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.