Researchers at Princeton University have developed the first commercially viable calcium titanite solar cells, marking an important milestone for an emerging renewable energy technology, according to the latest issue of the journal Science. The team expects their device to operate for around 30 years at more than the industry standard, well above the 20-year lifetime threshold for solar cells.
Not only is the device durable, it also meets common energy efficiency standards. It is the first of its kind to rival the performance of silicon-based cells.
Perovskites are semiconductors with a special crystal structure that are ideal for use in solar cell technology. They can be made at room temperature and use far less energy than silicon, making them cheaper and more sustainable to produce.
Early perovskite solar cells (PSCs) came out between 2009 and 2012 and lasted only a few minutes. The 2017 record was a year of battery operation under continuous lighting at room temperature, while the new device was able to operate in laboratory-like conditions for five years. The record-setting design highlights the durable potential of PSCs, particularly as a way to push solar cell technology beyond the limits of silicon, the researchers said.
This time, the researchers layered different materials to optimize light absorption while protecting the most vulnerable areas from exposure. They developed an ultrathin "two-dimensional capping layer" between two key ingredients: an absorbing perovskite layer and a charged layer made of copper salts and other substances. The goal is to prevent perovskite semiconductors from burning out within weeks or months.
The researchers also permuted the designs dozens of times, changing tiny details in the geometry and the number of overlay layers, and experimenting with dozens of material combinations. The experimental results show that the new device can exert more than 80% peak efficiency under the condition of an average temperature of about 35 ℃ and continuous lighting for at least 5 years.
In the long run, perovskites can be fabricated at room temperature, the researchers say, and their fabrication avoids burning large amounts of fossil fuels. But the development of new technologies does not mean that PSCs will largely replace silicon devices, but rather complement older technologies, making solar panels cheaper, more efficient, and more durable, and extending solar power into modern life More new areas.