Perovskites should capture light even more efficiently

Laboratories from the Swiss Federal Institute of Technology in Zurich (ETH), the Swiss Federal Institute of Technology Lausanne (EPFL) and the Swiss Federal Laboratories for Materials Science and Technology (Empa) have joined forces for a period of four years in the context of the AMYS project. They will jointly seek to develop solutions for the industrial processing of perovskite crystals, further details of which can be found in a press release issued by Empa. These can be used not only in solar cells, but also as lighting, as the basis for photodetectors in medical imaging or as sensors in smartwatches to measure heart rates and blood oxygen levels, for example.

An industrial manufacturing process for perovskite thin films is required. The team of perovskite specialists headed up by Ayodhya N. Tiwari and Fan Fu from the Laboratory for Thin Films and Photovoltaics at Empa are looking for a flexible perovskite photodetector and solar cells. Chih-Jen Shih’s team from the Nanomaterials Engineering Research Group at ETH Zurich is seeking to build perovskite LEDs that generate light with a selected high level of color accuracy. Finally, Christophe Ballif from EPFL and his team are looking for particularly efficient tandem solar cells that consist of silicon on the underside and a semi-transparent perovskite layer on the top.

The EPFL team already achieved a world record back in July: its efficiency of 31 percent had previously been achieved with other semiconductor cells, but these are around 1,000 times more expensive to produce. The EPFL researchers are now focused on developing a dry vapor-based process for the vapor deposition of perovskite crystals. Meanwhile, the Empa team has further developed the wet process and is therefore looking for a green approach for the industrial production of perovskite cells without the use of toxic solvents. mm