Researchers Develop Lead Absorbing Technology for Solar Perovskite Cells

The researchers at the National Renewable Energy Laboratory (NREL) have come up with a technology that could sequester the minuscule quantity of lead used in developing perovskite solar cells. This development might mark the beginning of an efficient emerging photovoltaic technology.

The perovskite solar cell is an emerging technology with great potential for the solar industry, but it still faces certain obstacles regarding the lead toxicity, which is impeding its wider adoption. While the chances are slim, there’s always a possibility of lead leakage when using this technology, which might pose a serious health risk when using perovskite solar cells in building-integrated photovoltaics.

The team of researchers at the NREL has developed a chemical approach for on-device sequestration of more than 96% of lead leakage caused by severe device damage.

“The light-absorbing layer on the perovskite solar cells contains a small amount of lead, and this could act as a deterrent when perovskite cells become commercially available,” says Kai Zhu, a senior scientist at NREL.

Zhu, along with Fei Zhang and Joseph Berry of NREL, Haiying He of Valparaiso University, and Xun Li and Tao Xu, worked on this development of this new technique.

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

It is important to note here that the efficiency of perovskite solar cells is close to 25%, and this could be cut into half if the lead is not used. While silicon solar panels use lead which is not soluble in water, lead used in perovskite cells can be dissolved in water, which is a significant concern. But the researchers at the NREL have come up with this technology that can sequester lead in case the cell is damaged.

To prevent the leakage of lead in case the cell is damaged, the researchers at NREL coated both sides of the cell with lead absorbing films, and then they cut the cell into half. The researchers then dipped the damaged cell in water and found that the lead absorbing film can prevent nearly 96% of lead from leaking into the water from the damaged cells.

Moreover, the addition of the film on the cell didn’t decrease the efficiency of the perovskite cells in any way, and this bodes well for the future.

The research was supported by the National Science Foundation and the U.S. Department of Energy’s Solar Energy Technologies Office.

Recently, Panasonic Corporation announced that it had achieved the world’s highest energy conversion efficiency of 16.09% for a perovskite solar module by developing a lightweight technology using a glass substrate and large-area coating method based on inkjet printing.

Previously, Mercom had reported that combining thin-film solar modules based on perovskite semiconductors with semiconductors made of copper, indium, gallium, and selenium (CIGS), solar module technology could cross the 30% efficiency mark, according to a study conducted by the Karls-ruhe Institute of Technology (KIT), Nice Solar Energy, and the Centre for Solar Energy and Hydrogen Research Baden-Württemberg (ZSW).


Image credit: NREL