Solar cell efficiency record achieved with tin halide perovskite

University of Queensland researchers have set a world record for solar cell efficiency with eco-friendly perovskite technology. A team led by Professor Lianzhou Wang has unveiled a tin halide perovskite (THP) solar cell capable of converting sunlight to electricity at a certified record efficiency of 16.65%. The research is published in the journal Nature Nanotechnology.

Working across UQ’s Australian Institute for Bioengineering and Nanotechnology and the School of Chemical Engineering, Professor Wang said the certified reading achieved by his lab was nearly one percentage point higher than the previous best for THP solar cells.

“It might not seem like much, but this is a giant leap in a field that is renowned for delicate and incremental progress,” Professor Wang said.

“The reading is in line with many silicon-based solar cells currently on the market but with the potential to be cheaper and quicker to make.

“We are thrilled with the record and also to be contributing to the progress of cost-effective renewable energy technology.”

Professor Wang’s THP solar cell record comes five years after his lab set a benchmark for power conversion efficiency in solar cells using another type of technology, quantum dots.

Research group member Dr. Dongxu He said many of the methods, processes and materials used to set the quantum dot record in 2020 inspired efforts to improve the performance of the highly promising THP thin-film solar cells.

“There is great commercial potential in THP solar cells because perovskite devices are more sustainable to produce than silicon-based solar cells,” Dr. He said.

“The benefit of THPs is that we’re dealing with more eco-friendly tin and not the toxic lead that is widely used in most of the perovskite solar cells, meaning they can be safely installed around the home.”

The use of tin precursor had previously been problematic because of the substandard quality of the fast-crystalline thin films used in manufacturing THP solar cells, leading to a dip in efficiency.

Dr. Peng Chen said the group overcame this hurdle by incorporating cesium ions to improve the microstructure and reduce defects in the THP film.

“This is what allowed us to reach a record level of efficiency while still having a product that would pass stringent environmental checks,” Dr. Chen said.

“I think we have a formula now that will only keep improving.”

Professor Wang said he was happy to see other researchers jostle to break the THP record because it ultimately meant better and more eco-friendly renewable energy technology.

He said the flexibility and versatility of THP cells—when coupled with improved efficiency—could make them the ideal candidate for household photovoltaic solar panels to be used both outdoors and indoors.

“Beyond solar panels, the approach we’ve used in this paper could also be used for other devices that require high-quality perovskite films like lasers, photodetectors, and transistors,” Professor Wang said.

“We could eventually see THPs used for engineering challenges, including as a lightweight solution to power electric aircraft—the sky really is the limit.”