Researchers from Korea's PEROLED, Seoul National University and Korea Basic Science Institute (KBSI), along with scientists from the UK's University of Cambridge, have reported an ultra-bright, efficient and stable perovskite LED made of core/shell perovskite nanocrystals with a size of approximately 10 nm, obtained using a simple in situ reaction of benzylphosphonic acid (BPA) additive with three-dimensional (3D) polycrystalline perovskite films, without separate synthesis processes.

During the reaction, large 3D crystals are split into nanocrystals and the BPA surrounds the nanocrystals, achieving strong carrier confinement. The BPA shell passivates the undercoordinated lead atoms by forming covalent bonds, and thereby greatly reduces the trap density while maintaining good charge-transport properties for the 3D perovskites.

Researchers from the University of Tokyo have made progress with the development of blue-emitting quantum dots, which is seen as highly challenging. They have shown that using a new bottom-up design strategy and self-organizing chemistry can help create a high purity blue-emitting QD material (with a narrow emission spectrum).

The newly developed QDs have a special chemical composition that combines both organic and inorganic substances, such as lead perovskite, malic acid, and oleylamine. The materials self-aligned into a cube of 64 lead atoms. The lead researcher, Professor Eiichi Nakamura, says that "it took over a year of methodically trying different things to find that malic acid was a key piece of our chemical puzzle".

It was recently reported that Contemporary Amperex Technology Limited (CATL), the Chinese manufacturer of energy devices, has filed to publicize its patents for the designs and manufacturing processes of several PV products.

The patents, which have been applied under the category of solar PV products, cover a backsheet, a transparent substrate, a perovskite PV cell, and a device design.

Researchers from Ulsan National Institute of Science and Technology (UNIST) have designed a photoelectrochemical cell for hydrogen production utilizing a high-performance organic–inorganic halide perovskite as a panchromatic absorber. The cell achieved a record high photocurrent density of 19.8 mA cm⁻².

Solar hydrogen production is one of the ultimate technologies needed to realize a carbon-neutral, sustainable society. However, an energy-intensive water oxidation half-reaction together with the poor performance of conventional inorganic photocatalysts have been big hurdles for practical solar hydrogen production. This study paves the way to improve solar hydrogen productivity.

Researchers from the University of Surrey, Swansea University, University of Sheffield, University of Cambridge and University of Oxford in the UK, China-based CAS and Canada's University of Toronto have fabricated an inverted perovskite solar cell by using a surface modulator that reportedly facilitates superior passivation on perovskite surfaces, increasing overall cell efficiency. As the surface modulator, the scientists tested two organic halide salts known as 4-hydroxyphenethylammonium iodide (HO-PEAI), and 2-thiopheneethylammonium iodide (2-TEAI).

“These modulators can affect the surface energy of the perovskite films,” the team explained. They explained that the two compounds can dramatically reduce non-radiative interfacial recombination. This can have a significant impact on electrical performance in perovskite cells, with implications for open-circuit voltage, short-circuit current, fill factor, and ultimately, power conversion efficiency. They reported that “2-TEAI showed a stronger interaction than HO-PEAI, forming a quasi-2D structure on the perovskite surface without further annealing.”

Researchers from the National Center for Nanoscience and Technology (NCSNT) of the Chinese Academy of Sciences (CAS) and Beihang University have developed a sulfonium cations-assisted intermediate engineering strategy to study the evolution of intermediates and the film properties of quasi-2D perovskites. The researchers developed a facile strategy for intermediate engineering by employing sulfonium cations to regulate the transformation of intermediates during the crystallization process and improve the film quality of quasi-2D perovskites.

The intermediates were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM) to reveal the composition and transformation process of the intermediates. The introduction of sulfonium cations inhibited the formation of unfavorable solvated lead iodide and promoted the formation of favorable perovskite intermediates with fiber-like morphology, which is conducive to the formation of high-quality perovskite crystals. The above effects have been confirmed in quasi-2D perovskite with different n values and 3D perovskites.

Researchers from the Ulsan National Institute of Science and Technology (UNIST) have teamed up with researchers from Daegu Gyeongbuk Institute of Science and Technology (DGIST) to develop a patterning technique for the production of perovskite nanocrystal displays which are ultra-thin and high-resolution. The production involves a very simple stamp-like printing process that will facilitate the commercialization of the new technique.

Double-layer transfer printing process with RGB pixelated arrays of PeNCs. Image from Science Advances

The technique reportedly enabled the team to produce a display with RGB pixel patterns of 2,550 pixels per inch, which is about 400 percent higher resolution than the latest high-end smartphones.

Scientists from the Ural Federal University (UrFU) and the Institute of Organic Synthesis of the Ural Branch of the Russian Academy of Sciences (along with their colleagues) have proposed a new type of material for transporting electrons in perovskite solar cells, which has a number of advantages.

The team reported that with the new material, they were able to achieve solar energy conversion efficiency of 12%. "The family of molecules we found carries electrons in PSCs slightly worse than the fullerenes used today, but they are about twice as cheap, much easier to produce, and have a number of other technological advantages," says Gennady Rusinov, associate professor at the Department of Organic Synthesis Technology of UrFU.

Researchers at the University of Helsinki are developing thin films for perovskite solar cells, and matching ALD processes. 

Doctoral Researcher Georgi Popov focuses on perovskites and atomic layer deposition (ALD). In 2019, He and his colleagues identified suitable chemicals and were able to design a reaction that enabled them to create a metal iodide coating through deposition for the first time. The researchers were able to demonstrate that this can actually be done through atomic layer deposition. The first successful trial was carried out with lead iodide, which was then processed into CCH₃NH₃PbI₃ perovskite through a further reaction. Later on, the researchers also developed ALD processes for caesium iodide and CsPbI₃ perovskite. 

Chinese perovskite solar technology company Renshine Solar (Suzhou) has announced achieving steady-state efficiency of 24.50% for all-perovskite tandem cell module, which it called 'a world record'.

It was reported that the efficiency was achieved for a perovskite module with an area of 20.25 cm², which exceeds that of perovskite single-junction components. The new efficiency level has been certified by Japan’s JET, it added without sharing other details.