New materials that can harvest and transmit light have exciting potential for technologies ranging from solar cells to televisions and display screens. In a new study, researchers have developed a new way to improve the stability (Improved stability of new materials for solar cells) and performance of one of these types of materials, called perovskites.
Researchers from the University of Missouri, in collaboration with scientists from the University of the Western Cape in South Africa and scientists from the Argonne National Laboratory of the United States Department of Energy (DOE), have developed a new way to hybrid perovskites. It is a combination of organic and inorganic semiconductor material that can be the basis of new solar cells or other electronic devices.
“Hybrid organic-inorganic perovskites have become an attractive material in electronics, especially in the last 10 years or so,” said MU Professor Suchismita (Suchi) Guha, the main author of the study. “They have been, in some cases, as efficient as silicon-based solar cells. In addition, they are more versatile than silicon and can be used to tune for different applications.
Guha and his collaborators have improved the method of producing halide perovskites. Previous methods for making these thin perovskites required liquid processing using a solvent, which allowed the film to collapse when exposed to air. Also, in this first production process, one of its cells undergoes changes in its structure, resulting in performance limitations under actual operating conditions. Using the new method, the researchers were able to prevent the change, keeping the affected molecules in a stable structure at high temperatures.
Furthermore, the new method made the perovskite gas more stable, making it suitable for potential cells. “Many studies have looked at ways to try to improve the stability of hybrid perovskites, including diffusion barriers, additive engineering and optimization of chemically inert electrodes, but this is one of the first studies to examine the growth process itself. ways to improve the final performance of the device,” said Guha.
To confirm the molecular structure of the perovskite material, Guha and his colleagues, including Argonne physicist Evguenia (Jenia) Karapetrova, used X-ray diffraction measurements at the Argonne Advanced Photon Source (APS), a DOE Office of Science employee. “Being able to characterize the perovskite structure in APS provides a unique window into the possibilities of this functional material,” Karapetrova said.
“Preventing changes in process seems to be the key to ensuring better device performance,” Guha said. “By supporting a stable system with an active thermal window, we are paving the way for better and more practical perovskites.”
