Major leap for stable high-efficiency perovskite solar cells

• Solar cells manufactured from products known as "perovskites" are catching up with the effectiveness of standard silicon-based solar cells. At the same time, they have advantages of inexpensive and also short energy payback time.

Nonetheless, such solar cells have troubles with stability-- something that scientists at Linköping University, along with worldwide collaborators, have now managed to solve. The results, released in Science, are a significant action forwards in the mission for next-generation solar cells.

"Our results open new opportunities to establish efficient and also stable solar cells. Additionally, they give new understandings right into just how the doping of organic semiconductors functions," claims Feng Gao, teacher in the Department of Physics, Chemistry as well as Biology (IFM) at Linköping University.

Perovskites are crystalline materials with huge capacity to add to solving the globe's power shortage. They are cheap to make, with high effectiveness and also low weight. Nevertheless, the perovskite solar cells can degrade swiftly, as well as it has not been possible to build high-efficiency perovskite-based solar cells with the required stability.

"There appears to be a trade-off between high efficiency and also stability in perovskite-based solar cells. High-efficiency perovskite solar cells have a tendency to reveal low stability, and also vice versa," states Tiankai Zhang, a postdoc at IFM as well as one of the primary writers of the article published in Science.

When solar energy is converted into electrical energy in perovskite-based solar cells, one or more charge transportation layers are usually required. These lie straight next to the perovskite layer in the solar cell. The organic cost transportation layers often need auxiliary molecules in order to work as planned. The material is referred to as being "doped".

One doped transport layer called Spiro-OMeTAD is a criteria in perovskite solar cells, and provides record power conversion effectiveness. But the here and now method made use of to dope Spiro-OMeTAD is slow, and triggers the stability issue of perovskite solar cells.

"We have now taken care of to eliminate the trade-off that has hindered advancement, making use of a new doping strategy for Spiro-OMeTAD. This makes it possible for us to get both high efficiency and also excellent stability," states Tiankai Zhang.

An additional major author of the article, Feng Wang, is a jr speaker at IFM. He points out that perovskite-based solar cells can be utilized in many ways, and have numerous areas of applications.

"One benefit of using perovskites is that the solar cells made are thin, which means that they are light and flexible. They can also be semi-transparent. It would certainly be possible, for example, to use perovskite-based solar cells onto large windows, or structure façades. Silicon-based solar cells are as well heavy to be made use of by doing this," states Feng Wang.