Researchers at Linköping University, in collaboration with colleagues in China, have developed a tiny unit that is both an optical transmitter and a receiver. "This is highly significant for the miniaturization of optoelectronic systems," says LiU professor Feng Gao.

Chunxiong Bao, postdoc at Linköping University, types in a sentence on a computer screen, and the same sentence immediately appears on the neighboring screen, optically transferred from one diode to another. The diode is made from perovskite.

University of Groningen scientists are investigating in situ how lead-free perovskite crystals form and how the crystal structure affects the functioning of the solar cells, as part of their quest to find alternatives to lead-based perovskites.

The best results in solar cells have been obtained using perovskites with lead as the central cation. As this metal is toxic, tin-based alternatives have been developed, for example, formamidinium tin iodide (FASnI₃). This is a promising material; however, it lacks the stability of some of the lead-based materials. Attempts have been made to mix the 3D FASnI₃ crystals with layered materials, containing the organic cation phenylethylammonium (PEA). "My colleague, Professor Maria Loi, and her research team showed that adding a small amount of this PEA produces a more stable and efficient material," says Assistant Professor Giuseppe Portale. "However, adding a lot of it reduces the photovoltaic efficiency".

Oxford PV recently stated that it hopes to deliver perovskite-silicon tandem solar cells to high end solar module manufacturers in the first half of 2021, now less than a year away.

The group expects these solar cells to have an efficiency between 26-27%, to increase in efficiency by 1% per year as the company improves its manufacturing techniques. It was said that initially, a 400 watt 60-cell solar module will probably be available.