New materials that can both harvest and emit light offer exciting potential for technologies that range from solar cells to TV and display screens. In a new study, researchers have developed a new way of enhancing the stability and performance of a particular type of these materials, called perovskites.
Researchers from the University of Missouri, in collaboration with scientists from the University of Western Cape in South Africa and physicists at the U.S. Department of Energy’s (DOE) Argonne National Laboratory, have developed a new way to make hybrid perovskites. These are a combination of organic and inorganic semiconducting materials that could form the basis of new solar cells or other electronic devices.
“Organic-inorganic hybrid perovskites have become increasingly attractive to the materials and electronics communities, especially over the past 10 years or so,” said MU professor Suchismita (Suchi) Guha, the lead author of the study. “They have become, in some cases, as efficient as silicon-based solar cells. Additionally, they are also much more versatile than silicon and can be used and tuned for a broad array of applications.”
Guha and her collaborators improved the methods for making lead halide perovskites. Previous techniques for making these thin-film perovskites required liquid processing using solvents, which rendered the films susceptible to degradation when exposed to air. Additionally, with this prior manufacturing process, one of its molecules undergoes a change to its structure, causing performance limitations in real-world operating conditions.
With the new technique, the researchers were able to prevent the change, holding the affected molecule in a stable structure throughout a large temperature range. Additionally, the new technique rendered the perovskite air stable, making it appropriate for a potential solar cell.
“There have been many studies that have looked at ways to try to improve the stability of hybrid perovskites, including diffusion barriers, additive engineering, and chemically inert electrode optimization, but this is one of the first studies to look at the growth method itself as a way to boost the final performance of the device,” Guha said.
To confirm the molecular structure of the perovskite material, Guha and her colleagues, including Argonne physicist Evguenia (Jenia) Karapetrova, used X-ray diffraction measurements at Argonne’s Advanced Photon Source (APS), a DOE Office of Science user facility.
“Being able to characterize the perovskite structure at the APS provides a unique window into the possibilities of this functional material,” Karapetrova said.
“Preventing the phase change seems to be the key to ensure improved device performance,” Guha said. “By maintaining a stable structure throughout the operating temperature window, we show the way to an improved and potentially useful perovskite.”
A paper based on the study was published in ACS Applied Electronic Materials.
About the Advanced Photon Source
The U. S. Department of Energy Office of Science’s Advanced Photon Source (APS) at Argonne National Laboratory is one of the world’s most productive X-ray light source facilities. The APS provides high-brightness X-ray beams to a diverse community of researchers in materials science, chemistry, condensed matter physics, the life and environmental sciences, and applied research. These X-rays are ideally suited for explorations of materials and biological structures; elemental distribution; chemical, magnetic, electronic states; and a wide range of technologically important engineering systems from batteries to fuel injector sprays, all of which are the foundations of our nation’s economic, technological, and physical well-being. Each year, more than 5,000 researchers use the APS to produce over 2,000 publications detailing impactful discoveries, and solve more vital biological protein structures than users of any other X-ray light source research facility. APS scientists and engineers innovate technology that is at the heart of advancing accelerator and light-source operations. This includes the insertion devices that produce extreme-brightness X-rays prized by researchers, lenses that focus the X-rays down to a few nanometers, instrumentation that maximizes the way the X-rays interact with samples being studied, and software that gathers and manages the massive quantity of data resulting from discovery research at the APS.
This research used resources of the Advanced Photon Source, a U.S. DOE Office of Science User Facility operated for the DOE Office of Science by Argonne National Laboratory under Contract No. DE-AC02-06CH11357.
Argonne National Laboratory seeks solutions to pressing national problems in science and technology. The nation’s first national laboratory, Argonne conducts leading-edge basic and applied scientific research in virtually every scientific discipline. Argonne researchers work closely with researchers from hundreds of companies, universities, and federal, state and municipal agencies to help them solve their specific problems, advance America’s scientific leadership and prepare the nation for a better future. With employees from more than 60 nations, Argonne is managed by UChicago Argonne, LLC for the U.S. Department of Energy’s Office of Science.
The U.S. Department of Energy’s Office of Science is the single largest supporter of basic research in the physical sciences in the United States and is working to address some of the most pressing challenges of our time. For more information, visit https://energy.gov/science.