Highly efficient perovskite solar cell with decent long-term durability unveiled
Organic solar cells with perovskite have outstanding properties. They can convert sunlight into electricity with an efficiency of 20 percent. Because they are also translucent, a conventional silicon-based solar cell can be mounted underneath.
Together, such a tandem can even achieve well over 30 percent efficiency. There are also perovskite solar modules that operate at an almost stable performance level for 25 years. The only thing that has not yet been available is a combination of performance and durability, which a development by the Hong Kong University of Science and Technology can change.
A new material or rather a new additive in the form of halides with their extremely high electronegativity ensures a unique crystal structure and high efficiency at the same time.
New structure, familiar technology
This also results in a modified surface, which remains the sore point and must be sealed as perfectly as possible. Here, the researchers concentrated on different amines, basically ammonia with hydrocarbon appendages, and applied them in various combinations for passivation.
And they were quite successful: the new type of cell completed the typical long-term test for photovoltaic modules with 95 percent of its original performance. Depending on the specific structure, this was just under 20 percent. In comparison, the currently longest-lasting perovskite cells can only reach 10 to 12 percent efficiency. Taking into account the usual deterioration in outdoor conditions compared to laboratory tests, there is still an outstanding increase in efficiency of over 50 percent.
At the same time, the surface sealing technology is based on the same principle and procedure as the optimization of semiconductor surfaces. According to the authors of the study, industrial production should therefore be unproblematic.
