Phys.org March 31, 2022 While analyzing the structure and optical properties of a common lead-halide hybrid perovskite an international team of researchers (USA – North Caroline State University, France) noticed the formation of polarons in these materials. Their analysis showed that formation of large polarons creates a thermal vibrational noise filter mechanism that they called ‘Quantum Analog of Vibration Isolation,’ or QAVI, which is like a shock absorber protecting the dipoles. When they are protected by the shock absorbers, the dipoles can synchronize and exhibit superfluorescence. According to the researchers, QAVI is an intrinsic property that exists in certain materials, […]
Tag Archives: Perovskites
UCLA materials scientists lead global team in finding solutions to biggest hurdle for solar cell technology
EurekAlert March 15, 2022 Optoelectronic devices consist of heterointerfaces formed between dissimilar semiconducting materials. The relative energy level alignment between contacting semiconductors determinately affects the heterointerface charge injection and extraction dynamics. For perovskite solar cells (PSCs), the heterointerface between the top perovskite surface and a charge-transporting material (CTM) is often treated for defect passivation to improve PSC stability and performance. However, such surface treatments could also affect the heterointerface energetics. An international team of researchers (USA – UCLA, UC Irvine, Turkey, South Korea, Taiwan) has shown that surface treatments may induce a negative work function shift (i.e., more n-type), which […]
Scientists find ways to help perovskite solar cell ‘self-healing’
Nanowerk December 28, 2021 Organic-inorganic hybrid perovskite solar cells, considered as a competitive alternative to conventional silicon solar cells, are prone to degrade when exposed to air. An international team of researchers (China, Greece, Australia) introduced PVP to the methylammonium lead iodide perovskite precursor. It can control crystal growth and endow the devices with self-healing ability in a moisture environment. When it was introduced in perovskite solar cells, it acted as a protective armor with an automatic blood backflow effect against water vapor. In addition, PVP can improve crystal growth with fewer defects and larger grains…read more. TECHNICAL ARTICLE
These Engineers May Have Come Up With The Perfect Material For Unbreakable Screens
Science Alert November 5, 2021 Lead halide perovskite (LHP) semiconductors show exceptional optoelectronic properties. Barriers for their applications, however, lie in their polymorphism, instability to polar solvents, phase segregation, and susceptibility to the leaching of lead ions. An international team of researchers (Australia, Slovenia, China, UK, France, Japan, Singapore) has developed a process to wrap or bind the nanocrystals in porous glass to stabilize the material, enhance its efficiency, and inhibit the toxic lead ions from leaching out from the materials. The product showed high stability when exposed to heat, light, air, and humidity, and was able to retain 80 […]
Perovskite memory devices with ultra-fast switching speed
Science Daily June 22, 2021 Halide perovskite-based memory devices have limitations of slow switching speed which hinder their practical application in memory devices. Researchers in South Korea have successfully developed ultra-fast switching memory devices using halide perovskites by using a combined method of first-principles calculations and experimental verification. From a total of 696 compounds of halide perovskites candidates, Cs3Sb2I9 with a dimer structure was selected as the best candidate for memory application. They fabricated memory devices using the dimer-structured Cs3Sb2I9 to verify the calculation results. The devices were operated with an ultra-fast switching speed of 20 ns, which was more […]
A new spin on energy-efficient electronics
Phys.org March 30, 2021 An international team of researchers (USA – University of Wisconsin, University of Nebraska, Cornell University, Lawrence Berkeley National Laboratory, Argonne National Laboratory, South Korea, UK, Norway, Ireland) designed a new structure based on antiperovskites to manipulate the flow of spin information without moving the electrons’ charges through the material. Through X-ray diffraction they figured out at what point the structure of the material changed, indicating the emergence of the necessary arrangement of electronic spins. The material develops a magnetic order a little above room temperature. According to the researchers the ability to manipulate the arrangement of […]
Engineers make a promising material stable enough for use in solar cells
Science Daily April 29, 2020 Inherently soft crystal lattice of Halide perovskites allows greater tolerance to lattice mismatch, making them promising for heterostructure formation and semiconductor integration. However, their high intrinsic ion mobility, which leads to interdiffusion and large junction widths and their poor chemical stability, epitaxial growth of atomically sharp heterostructures of halide perovskites has not yet been achieved. An international team of researchers (USA – Perdue University, MIT, UC Berkeley, Lawrence Berkeley National Laboratory, China) has developed a strategy to substantially inhibit in-plane ion diffusion in two-dimensional halide perovskites by incorporating rigid π-conjugated organic ligands. They have demonstrated […]