Large-scale solar cell manufacturing could be possible thanks to a recent perovskite fabrication technique
Scientists in Taiwan and the United States have discovered a fundamental change to the manufacturing method that could make mass manufacture of greater-performance perovskite solar cells even simpler. Leeyih Wang of National Taiwan University, as well as colleagues, invented the technique, which increased the power conversion efficiency as well as the operating lifespan of the perovskite mini-module.
Their breakthrough could pave the way for large-scale production of perovskite solar cells, rendering them a formidable competitor to established silicon-based cells. Perovskite components are commonly regarded as one of the most exciting low-cost and large-area solar cell choices. Latest studies have shown conversion efficiencies as large as 22% over fields of 0.5 cm2 due to their exceptional optoelectronic properties. Even so, the thin perovskite films’ difficult processing conditions have hampered comparable performances on the larger scales so far.
The current fabrication method entails dripping antisolvent onto the perovskite precursor, which has been spin-coated onto the substrate. This technique should be able to produce films with consistent, high-quality crystal structures. However, the procedure must be closely regulated, as well as the antisolvent should be added within a 9-second time frame after the initial deposition. Otherwise, the resultant perovskite film can be rough and irregular, reducing its solar cell efficiency. When the size of the film becomes bigger, this method becomes more complex to execute.
To address this issue, Wang’s team, which included Los Alamos National Laboratory researchers, developed a technique that greatly extended the post-deposition timeframe. In their experiment, they used sulfolane as antisolvent, which permitted them to be able to fabricate uniform, high-quality, large-area perovskite films. They researched the chemical processes involved using a mixture of X-ray diffraction as well as infrared spectroscopy to analyze the molecular pathways responsible for this progress.
They discovered that hydrogen bonding that is between sulfolane molecules, as well as perovskite precursor ions, greatly delayed the crystallization phase, increasing the antisolvent addition timeframe to 90 seconds. This allowed for the formation of compressed, highly uniform crystal structures under far less demanding processing conditions. Wang, as well as colleagues, created a perovskite solar cell mini-module that does have a 36.6 cm2 active area to prove this enhancement.
After functioning for 250 hours at about 50 °C – the moment at which it obtained the maximum power – their device attained a very decent power conversion efficiency of more than 16 percent and retained approximately 90% of its preliminary performance. The high efficiency, as well as the long operational lifetime of perovskite solar cells, pave the way for large-scale production in far more adaptable manufacturing conditions. Wang and his colleagues hope that the technology will be widely available commercially soon. It will even be a worthy contender to the silicon-based solar cells, boosting renewable solar energy prospects.