August 2019

Researchers from the Australian National University (ANU) have reportedly broken new ground in solar cell energy efficiency and in the process provided a glimpse of the technology's future. The researchers have a announced a record of 21.6% efficiency, which they say is the highest achieved for perovskite cells above a certain size.

Associate Professor Thomas White says as a comparison, typical solar panels being installed on rooftops right now have efficiencies of 17-18%. 'There are three things you're trying to achieve with solar cells, you're trying to make them efficient, stable and cheap," he said. "Perovskites are the future of solar cells."

Researchers from the KAUST Solar Center have monitored the impact of compositional changes on the structural organization and photovoltaic properties of perovskite thin films in situ. The team has reached a conclusion that may benefit perovskite solar cells in the future - that changes in composition affect light-harvesting layer crystallization and perovskite solar cell efficiency.

Sequence of fabrication of a perovskite thin film from precursor solution to solid film via the spin-coating deposition process. Image by KAUST

Solar cell performance and stability depend on the morphology of the thin films, especially their ability to crystallize in the so-called photoactive α-phase. Perovskites that contain lead tend to combine various halides, such as the anionic forms of bromine and iodine, with mixtures of methylammonium, formamidinium, cesium and other cations. These have led to record conversion efficiencies and thermal stabilities compared with their single-halide, single-cation analogs. However, these mixed-halide, mixed-cation perovskite films have been characterized only through ex-situ postdeposition techniques. This limits the understanding of the mechanisms that govern their growth from their sol-gel precursor to their solid state and stalls attempts to improve device performance and stability.

Researchers at Tohoku University in Japan have found a new way to successfully detect the efficiency of crystal semiconductors. For the first time, the team used a specific kind of photoluminescence spectroscopy, a way to detect light, to characterize the semiconductors. The emitted light energy was used as an indicator of the crystal's quality. This method will potentially yield more efficient light-emitting diodes (LEDs), solar cells and several other advances in electronics.

Schematic of the ARPL measurement technique

"For further development of perovskite-based devices, it is essential to quantitatively evaluate the absolute efficiency in high-quality perovskite crystals without assuming any predefined physical model is of particular importance," said corresponding author Kazunobu Kojima, Associate Professor at Tohoku University, Japan. "Our method is new and unique because previous methods have relied on efficiency estimation by model-dependent analyses of photoluminescence."

Researchers from Zhejiang University, the Beijing Institute of Technology and Nanjing Tech University in China, Argonne National Laboratory in the U.S, University of Cambridge in the UK have combined perovskite nanoparticles with 2D perovskites to double the efficiency of blue LEDs.

Bromide perovskite films consisting of nanoparticles embedded within 2-D perovskite layers produce blue LEDs with a record-high efficiency of 9.5%

While the device only glows for a few minutes, the work is still considered 'a big step toward the development of high-performance blue perovskite emitters' says Jianjun Tian of the University of Science and Technology in Beijing, who was not involved in the work. 'The efficiency of these blue perovskite LEDs is already higher than that of the commercially available blue organic LEDs.'

An international research team, including scientists from Shanghai Jiao Tong University, the Ecole Polytechnique Fédérale de Lausanne (EPFL), and the Okinawa Institute of Science and Technology Graduate University (OIST), has found a stable that efficiently creates electricity and could be extremely beneficial for perovskite solar cells.

The researchers show how the material CsPbI_3, an inorganic perovskite, has been stabilized in a new configuration capable of reaching high conversion efficiencies. This configuration is noteworthy as stabilizing these materials has historically been a challenge.

India's Ministry of New and Renewable Energy (MNRE) has invited project proposals from industrial players, startups and R&D labs for high-efficiency perovskite solar cells, solar panel recycling, hybrid inverters and new applications that combine solar and storage, among others.

Specific R&D areas include the processes for segregating different components of end-of-life PV modules, as well as the recycling of glass. Research will also focus on grid-tied inverters that are suitable for the Indian grid and the country's environmental conditions, in addition to hybrid inverters with capacities of up to 500 KVA, electronics for HT grid stabilization that incorporate storage batteries, and high-efficiency perovskite solar cells on single- and multicrystalline silicon substrates.

Researchers at the Tokyo Institute of Technology (Tokyo Tech) have designed a new strategy to make efficient perovskite-based LEDs with improved brightness by leveraging the quantum confinement effect.

(A) Photoluminescence and (B) electroluminsecence in low-dimensional and 3D perovskite-based devices

Devices that emit light when an electric current is applied, are referred to as electroluminescent devices, which have become orders of magnitude more efficient than the traditional incandescent light bulb. Light-emitting diodes (LEDs) make for the most notable and prevalent category of these devices. Many additional types of LEDs also exist.

Saule Technologies announced that it finished construction of the first stage of its new cleanroom. The entire working area will be around 430 m², and should be complete in a couple of weeks.

Saule Technologies aims to launch a prototype production line by Q4 2019. The production line will include a modular system of printers with an annual production capacity of 40,000 sqm. In 2020, the company aims to increase the annual production capacity to 200,00 sqm.

After forming a strategic partnership in March 2019 between Meyer Burger and Oxford Photovoltaics, Meyer Burger has announced that it has received its first order from Oxford Photovoltaics (Oxford PV), for a heterojunction (HJT) manufacturing line including necessary adaptions enabling the upgrade to perovskite-on-HJT tandem technology.

The order for the upgrade itself will reportedly follow later this year. The current contract volume is about CHF 20 million and provides Oxford PV with an initial manufacturing capacity of 100 MW with plans to expand tandem solar cell production capacity to 250 MW by the end of 2020.

Researchers from the University of Florida and Pacific Northwest National Laboratory set out to improve global nuclear security by enhancing radiation detectors, and discovered, after evaluating a diverse list of over 60 candidates for alternative semiconductor compounds, that a hybrid organic-inorganic perovskite has the highest potential to succeed.

Better sensors can improve equipment used for detecting and identifying radioactive materials. (Image credit: Pacific Northwest National Laboratory)

The scientists reported that the identification of better sensor materials and the development of smarter algorithms to process detector signals are essential to enhance radiation detectors. Paul Johns, Physicist, University of Florida, said: "The end users of radiation detectors don't necessarily have a background in physics that allows them to make decisions based on the signals that come in. The algorithms used to energy-stabilize and identify radioactive isotopes from a gamma ray spectrum are therefore key to making detectors useful and reliable".