Next-generation solar materials are cheaper and greener to produce than traditional silicon solar cells, but there are still obstacles to producing robust devices that can withstand realistic conditions. A new technology developed by an international team of scientists simplifies the development of efficient and durable perovskite solar cells, named for their unique crystal structure that effectively absorbs visible light.
Scientists, including Penn State faculty member Nelson Zadeh, write in Nature Energy about the new method for creating more powerful perovskite solar cells that still achieve a high efficiency of 21.59% for converting sunlight into electricity.
Perovskites are a promising solar technology because the cells can be produced at room temperature using less energy than traditional silicon materials, making them less expensive and more durable, said Zadeh, an assistant professor of energy and mineral engineering at John & Willie Lyons University. Production. . Department of Energy and Mineral Engineering staff and co-author of the study.
But the main filters used to make these devices are hybrid organic-inorganic metal halides, organic components sensitive to moisture, oxygen and temperature, and exposure to ambient conditions can cause rapid performance degradation, the scientists said.
One solution is to rely on completely inorganic perovskite materials, such as cesium lead iodide, which have good electrical properties and good environmental protection. However, this material is polymorphic, i.e. it contains multiple phases with different crystal structures. According to scientists, both photovoltaic levels are good for solar cells, but at room temperature, they can easily change to undesirable levels of non-photovoltaics, leading to defects and reduced efficiency of solar cells.
By combining two polymorphic forms of cesium and lead iodide, scientists say they have created a different phase that prevents unwanted phase transitions. By stacking different semiconductor materials, different images are created, like the layers in a solar cell, with different optical properties. These compounds in solar devices can be designed to help them absorb more of the sun's energy and convert it more efficiently into electricity.
"The great thing about this work is that it shows that it is a promising way to make monolithic solar cells from two polymorphic forms of the same material," he said. "This improves the stability of the material and prevents the transition between the two phases. By creating a unique interface between the two phases, electrons can easily pass through the device, increasing the efficiency of energy transfer. We have confirmed this in this work."
The researchers produced a device that achieved a power conversion efficiency of 21.59%, one of the highest for this type of approach, and had excellent stability. Dzadeh said the devices retained more than 90% of their original efficiency after 200 hours of storage in the atmosphere.
"From laboratory scale solar cells to real-world solar cell designs, our solar cell design showed a power conversion efficiency of 18.43% for a solar array larger than 7 square inches (18.08 square cm)," said Dzadeh. "These initial results highlight the potential of our approach to fabricate very large perovskite solar cell modules and reliably assess their stability."
Zad presents the heterojunction structure and electronic properties at the atomic level, and combines two photoactive phases to form a stable and coherent surface structure that improves efficient charge separation and transfer. .
Zadeh's colleagues at Chaonam University in South Korea developed a unique double deposition method to produce the device. One stage is hot air, the other three sources of heat vapor. Sawanta S., a research professor at Cheungnam University in South Korea and lead author of the study. Malin
"We believe that the dual-deposition method we developed in this work is essential for the production of highly efficient and stable perovskite solar cells in the future," said Nelson Zadeh, assistant professor of energy and mineral engineering in the John & Wiley Family Department.
The researchers found that the binary deposition method could pave the way for more solar cells based solely on inorganic perovskite or other halogenated perovskite components. In addition to expanding the technology to different compounds, future work will include improving the efficiency of phase-heterogeneous cells under real-world conditions and scaling them up to conventional solar cells, the researchers said.
"With this approach, we believe that the efficiency of this material can be increased by more than 25% in the near future," said Dzadeh. "If we can do this, business will be very close."
More information: Sawanta S. Mali et al., Phase Change Inorganic Perovskite Solar Cells Achieve Efficiencies Above 21.5%, Nature Energy (2023). DOI: 10.1038/s41560-023-01310-y
Citation: Scientists develop new method to produce stable, efficient solar cells Retrieved October 28, 2023 from https://phys.org/news/2023-10-scientists-method-stable- - Area of effectiveness. - The next generation.html
This file is copyright protected. No part may be reproduced without written permission except for the bona fide purposes of personal study or research. The content is for informational purposes only.
