New hybrid material allows perovskites to go lead-free

A new type of material for next-generation solar cells eliminates the need to use lead, which has been a major roadblock for this technology.

Solar cells that incorporate the mineral perovskite have been a focus of attention since the material was first shown to work in 2009. Solar cells that are built using this material are more efficient than current solar panels, which can capture 15% to 18% of solar energy on average. In contrast, perovskite solar cells have been found to capture as much as 28% of solar energy.

But there are major obstacles to the commercial use of perovskite materials, as they are not stable and contain water-soluble lead, which is a health hazard.

Now, a team of scientists and engineers led by Letian Dou, assistant professor of chemical engineering at Purdue University, has developed a sandwich-like material that incorporates similar organic and inorganic materials to those found in perovskites. But this hybrid structure, which is described in a paper in Nature Chemistry, doesn't use lead and has a much improved stability.

"These structures are very exciting," Dou said. "The sandwich structures are like semiconductor quantum wells that are widely used today in many electronic and optoelectronic devices, but they are much easier to produce and more tolerant to defects,"

In a recent paper published in the Journal of the American Chemical Society, the scientists reported incorporating this material into a field-effect transistor, an essential component of many electronic devices.

According to Yao Gao, lead author of both research papers and a postdoctoral fellow in Dou's research group, the new organic-inorganic hybrid perovskite materials are cheaper and perform better than a traditional inorganic semiconductor. The new material's design strategy could also serve as a blueprint for many other functional hybrid materials.

"Solar cells, as many people have demonstrated, can be highly efficient," Gao said. "With our new technology, we can make the hybrid perovskite materials intrinsically more stable. By replacing the toxic lead, these new materials are better for the environment and can also be safely used for bioelectronics sensors on the body."

This story is adapted from material from Purdue University, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier. Link to original source.