Researchers at the U.S. Department of Energy’s National Renewable Energy Laboratory (NREL) and the University of Toledo have found that perovskite solar cells should be subjected to a combination of stress tests simultaneously to best predict how they will function outdoors.

The team used a state-of-the-art p-i-n PSC stack (with PCE up to ~25.5%) to show that indoor accelerated stability tests can predict 6-month outdoor aging tests. Device degradation rates under illumination and at elevated temperatures are most instructive for understanding outdoor device reliability. The team also found that the indium tin oxide (ITO)/self-assembled monolayer (SAM)-based hole transport layer (HTL)/perovskite interface most strongly affects the device operation stability. Improving the ion-blocking properties of the SAM HTL increases averaged device operational stability at 50°C–85°C by a factor of ~2.8, reaching over 1000 h at 85°C and to near 8200 h at 50°C with a projected 20% degradation, which is among the best to date for high-efficiency p-i-n PSCs.

Researchers from Pohang University of Science and Technology (POSTECH), Chinese Academy of Sciences (CAS) and University of Electronic Science and Technology of China have developed perovskite transistors through the use of three distinct perovskite cation processes. 

The team showed that pure-tin perovskite thin-film transistors can be created using triple A cations of caesium–formamidinium–phenethylammonium. This approach reportedly leads to high-quality cascaded tin perovskite channel films with low-defect, phase-pure perovskite/dielectric interfaces.

Researchers from Japan's Tohoku University and University of Tsukuba have reported a breakthrough in the development of non-volatile phase change memory−a type of electronic memory that can store data even when the power is turned off−using a perovskite-derivative nickelate material.

Until now, phase change memory has primarily been developed using chalcogenides, a group of materials known to exhibit reversible electrical changes when they transition between their crystalline and amorphous states. However, in their recent study, the researchers reported thermally reversible switching of room-temperature electrical resistivity in a layered nickelate−potentially offering better performance and superior sustainability.

Researchers from the University of Toronto, Peking University and Soochow University have studied the origins of unwanted emission in monolayer perovskite LEDs when the active layer thickness approaches ~5 nm and found that using available fabrication techniques results in a rough perovskite/HTL interface which leads to punch-through and direct electrical interaction between HTL and ETL (electron-transporting layer), and consequently, to undesired exciplex emission in LEDs.

The team sought to control monolayer interfaces in Rec.2100 primary blue perovskite LEDs and recognized that a well-defined, ordered, and compact monolayer film could suppress HTL/ETL interaction. They reasoned that this could be achieved if they could alter the polarity of the CsPbBr₃ c-NC surface and thereby induce perovskite self-assembly down to the monolayer limit [i.e., self-assembled monolayer (SAM)] through the use of an HTL-compatible ligand. Self-assembled films with ordered nanocrystal arrangement maximize the interactions between nanocrystals and provide homogeneity needed for monolayer films with ~5-nm thickness.

Researchers from the Indian Institute of Technology Bombay and Germany's Helmholtz Young Investigator Group FRONTRUNNER IEK5-Photovoltaik have designed an inverted perovskite solar device that uses a self-assembled monolayer to suppress nonradiative recombination at the interface between the perovskite absorber and the hole transport layer. The team reported high efficiency for the cell and say it was also able to retain the initial efficiency rating for 3,000 h.

The inverted perovskite solar cell was based on a hole transport layer (HTL) made of a phosphonic acid called methyl-substituted carbazole (Me-4PACz).

Researchers from Princeton University and the King Abdullah University of Science and Technology (KAUST) have connected silicon solar cells with perovskite ones in a tandem solar cell to not only boost overall efficiency, but also to strengthen stability. The results show that the connection protects the frail perovskite solar cell from voltage-induced breakdown while attaining greater efficiencies than either cell can achieve on its own.

The team demonstrated that the tested perovskite/silicon tandem devices are considerably more resilient against reverse bias compared with perovskite single-junction devices. The origin of such improved stability stems from the low reverse-bias diode current of the silicon subcell. This translates to dropping most of the voltage over the silicon subcell, where such a favorable voltage distribution protects the perovskite subcell from reverse-bias-induced degradation.

Researchers from Linköping University in Sweden and Universidad de Concepción in Chile recently designed a new type of random number generator for encryption, based on Perovskiye LEDs. The new technology could make digital information exchange safer, cheaper and more environmentally friendly and even pave the way for a new type of quantum communication.

To encrypt information, a random number generator is used, which can either be a computer program or the hardware itself. The random number generator provides keys that are used to both encrypt and unlock the information at the receiving end. Different types of random number generators provide different levels of randomness and thus security. Hardware is the safer option as randomness is controlled by physical processes. And the hardware method that provides the best randomness is based on quantum phenomena – what researchers call the Quantum Random Number Generator, QRNG.

Graphitic materials supplier First Graphene has announced an R&D collaboration with Greatcell Energy, trading as Halocell Energy, and the Queensland University of Technology (QUT) to commercialize perovskite solar cell fabrication. The project has received a Cooperative Research Centers Project (CRC-P) grant worth over AUD$2 million (around $USD1,300,000).

The research and development project is intended to commercialize ultra-low-cost, flexible perovskite solar cell fabrication using Halocell’s roll-to-roll production process at the company’s Wagga Wagga plant, First Graphene said in an announcement. Through the project, First Graphene plans to develop cost-effective graphene-based electrode replacements for high-cost conductor materials, such as gold and silver, used in cell manufacturing.

U.S-based retail solar brand Grape Solar has announced that it will be going into the perovskite PV R&D field, as it appointed Dr. Leon Dong as its head of the newly formed Solar Technology Research Center (STRC) in Eugene, Oregon.  

"This is a historical moment for us. Solar technology has improved significantly in the last decade, from efficiency and cost point of view, however, little has changed in terms of its form factor. The market demands for more flexible, lightweight, even more colorful solar products. We envision a future that would bring these kinds of technology to live in the next few years as the industry advances, and Grape Solar wants to excel in bringing new and improved technology products to our customers by making them in the United States. To achieve this goal, we need many young talents. Leon possesses the scientist mindset in the purest sense, which is rare to find these days." Commented Ocean Yuan, CEO of Grape Solar.

Researchers from Duke University, Purdue University,  Yale University, Lawrence Berkeley National Laboratory, Chinese Academy of Sciences (CAS), Westlake University and Huazhong University of Science and Technology have demonstrated that by limiting the arrangement of multiple inorganic and organic layers within crystals using a novel technique, they can regulate the energy levels of electrons and holes (positive charge carriers) within perovskites.

This tuning capability affects the materials’ optoelectronic properties and capacity to emit light of specific energies, as illustrated by their ability to function as a laser source.