The secret to removing one of the biggest barriers to the development of low cost solar ink is the use of perovskite.
Perovskite could make photovoltaic ink printing simple and cheap, almost as much as newspaper printing. Researchers at the University of Toronto, following the latest global research, have focused their work on the properties of these artificial crystals.
“Year after year, the cost of producing silicon has been drastically reduced,” says Professor Ted Sargent, solar technology expert and study author. “But perovskite allows us to use techniques already established in the printing industry for the production of solar cells at very low cost.”
Today, virtually all commercial solar cells are made of crystalline silicon sheets, the purity of which must be very high. To achieve this, an energy-intensive process is required, which requires temperatures above 1000 ºC, as well as the use of large amounts of hazardous chemicals.
In contrast, perovskite solar cells are based on a layer of tiny crystals – each about 1,000 times smaller than the width of a human hair – made from cheap materials. These raw materials can be easily mixed with liquids to form a kind of solar “ink”. So in the future, you can easily print with photovoltaic ink using a normal inkjet printer.
Hairen Tan and her team have successfully developed novel perovskite nanoparticles, which are coated with a layer of chlorine atoms, to help connect to the perovskite layer above the cell, allowing efficient extraction of electrons. This new manufacturing process for perovskite solar cells requires temperatures below 150 ºC.
In laboratory tests the results were encouraging, they managed to maintain more than 90% of the efficiency of perovskite solar cells after 500 hours of use.
+ Information: science.sciencemag.org