Perovskite-Info: the perovskite experts

Oxford University researchers attempted to understand what makes certain combinations of elements in the Periodic Table arrange as perovskite crystals and others not, and whether the number and nature of undiscovered pervoskites can be.

The team examined the Norwegian mineralogist Victor Goldschmidt's 1926 hypothesis known as the 'no-rattling' approach: that the formability of perovskites follows a simple geometric principle, namely: The number of anions surrounding a cation tends to be as large as possible, subject to the condition that all anions touch the cation. It basically means that if we describe a crystal using a model of rigid spheres, in a perovskite the spheres tend to be tightly packed, so that none can move around freely. Using elementary geometry, Goldschmidt's hypothesis can be translated into a set of six simple mathematical rules that must be obeyed by the ions of a perovskite.

Researchers at the Argonne-Northwestern Solar Energy Research Center (ANSER) have developed a new way to protect perovskite-based solar cells from water and stabilize them against heat. By carefully growing an ultrathin layer of metal oxide on a carbon coating, the researchers made a perovskite device that worked even after exposing it to a stream of water.

Solar cells are made up of layers, each with a specific duty. The perovskite layer absorbs sunlight, which can excite an electron. The electron could go back to where it started, unless it can be successfully extracted out of the absorbing layer quickly. For this device, the researchers placed a layer of PC61BM, a carbon-based material, on top of the perovskite, which has two roles.

Researchers at the Japan-based Okinawa Institute of Science and Technology Graduate University (OIST) have developed perovskite-based solar devices using a new perovskite material that is stable, efficient and relatively cheap to produce.

This material has several key features. First, it is completely inorganic – an important shift, because organic components are usually not thermostable and degrade under heat. Since solar cells can get very hot in the sun, heat stability is crucial. By replacing the organic parts with inorganic materials, the researchers made the perovskite solar cells much more stable. “The solar cells are almost unchanged after exposure to light for 300 hours,” says Dr. Zonghao Liu, an author on the paper.

Researchers from Northwestern University and Argonne National Laboratory research team have developed a perovskite-based next-generation device for nuclear radiation detection that could provide a significantly less expensive alternative to the detectors now in commercial use.

The high-performance material is used in a device that can detect gamma rays, weak signals given off by nuclear materials, and can efficiently identify individual radioactive isotopes. The new material also has the advantage of inexpensive production. Potential uses for the new device include more widespread detectors for nuclear weapons and materials as well as applications in biomedical imaging, astronomy and spectroscopy.

Oxford PV has announced it has secured a further £8.02 Million (around $11.2 USD) in funding from its existing investors including Statoil and Legal & General Capital, to continue the commercialization of perovskite-on-silicon tandem solar cell technology.

The funding will enable Oxford PV to continue to transfer its advanced perovskite-on-silicon tandem solar cell technology from the company’s lab in Oxford, UK to industrial scale processes and equipment at the company’s demonstration line in Brandenburg an der Havel, Germany. Oxford PV is working to fully optimize its commercial sized perovskite-on-silicon tandem solar cell technology, to ensure ease of integration into large scale silicon solar cell and module production. The company is closely collaborating with its development partner – a major manufacturer of silicon solar cells and modules.

Saule Technologies, Poland-based developer of perovskite solar cells ink-jet printed on thin foil, has issued an open call for companies interested in licence agreements for BIPV applications in Middle Eastern countries. This follows Saule's recent announcement of the first commercial contract in BIPV with Norwegian construction company Skanska.

Saule Technologies offers flexible licence-based cooperation opportunities for companies active in the Middle East, available for entities interested in the development, distribution and integration of Saule’s solar cells in BIPV applications. The subject of the licence is an opaque PV product with very high energy conversion efficiency which can be easily integrated with building facades, and an efficient, translucent perovskite cell in any color (so-called "solar window"). Conditional licence (Exclusive Licence and Non-Exclusive Licence) for the use of any future product can be granted for a chosen country or group of countries not covered by the licence agreement with another entity.

A multi-institutional team of researchers from the Department of Energy’s Oak Ridge National Laboratory, Hunan University and the University of Nebraska–Lincoln used photoluminescence measurements, along with neutron and x-ray scattering, to study the relationship between hybrid perovskite materials' microscopic structure and optoelectronic properties. Neutron scattering has revealed, in real time, the fundamental mechanisms behind the conversion of sunlight into energy in such materials, to gain a better understanding that will enable the design of better solar cells.

By examining the material under varying degrees of temperature, the researchers were able to track atomic structural changes and establish how hydrogen bonding plays a key role in the material’s performance. Unlike their singular silicon or germanium counterparts, hybrid perovskites are made of both organic and inorganic molecules. “The advantage of having both organic and inorganic molecules in a well-defined crystal structure means we can tailor the material by tuning either one group or the other to optimize the properties,” said Kai Xiao, a researcher at ORNL’s Center for Nanophase Materials Sciences. “But even though researchers have been studying these materials for several years, we still don’t fully understand on a fundamental level how the organic components are affecting the properties.”