September 2020

Researchers at Northwestern University have developed a new method for synthesizing halide perovskite nanocrystals.

The synthesis process for the halide perovskite nanocrystal arrays. Image from Science Advances

'This method could be used to create optical displays with 'true' reds, greens, and blues that completely outshine current LEDs,' said Northwestern's Chad A. Mirkin. 'From color purity to pixel density, these nano-LEDs point toward a potentially dramatic improvement over current LEDs.'

Researchers from Czech Republic's Charles University, University of Tennessee and Oak Ridge National Laboratory in the U.S have explored the dynamics of free holes in methylammonium lead tribromide (MAPbBr₃) single crystals using time-of-flight (ToF) current spectroscopy. The team's results provide insights on the charge transport properties of perovskite semiconductors.

By combining ToF spectroscopy and Monte Carlo simulation, three energy states were detected in the bandgap of MAPbBr₃. In addition, the team found the trapping and detrapping rates of free holes ranging from a few microseconds to hundreds of microseconds. It was revealed that a strong detrapping activity of traps exists.

Scientists from City University of Hong Kong (CityU) recently developed a novel method which can simultaneously tackle both the lead leakage issue of perovskite solar cells and the stability issue without compromising efficiency, paving the way for real-life application of perovskite photovoltaic technology.

Perovskite solar cells tend to contain lead components, which raise concerns for potential environmental contamination. "As the solar cell ages, the lead species can leak through the devices, e.g. through rainwater into the soil, posing a toxicity threat to the environment," explained Professor Alex Jen Kwan-yue, CityU's Provost and Chair Professor of Chemistry and Materials Science. "To put PVSCs into large-scale commercial uses, it requires not only high power conversion efficiency but also long-term device stability and minimized environmental impact."

A research team from the Shanghai Institute of Optics and Fine Mechanics has recently demonstrated perovskite CQDs (colloidal quantum dots) single-mode laser with good performance across the entire visible spectra range.

In this study, a composited microcavity was obtained through the conformal deposition of cesium lead halide perovskite (LHP) CQDs on a high quality individual sub-micron ZnO rod by dip-coating self-assembled techniques. A single-mode lasing with high quality factor and low threshold was obtained.

Researchers from King Abdullah University of Science and Technology (KAUST) have fabricated efficient, two-terminal monolithic perovskite-silicon tandem solar cells and tested them outdoors. The tandem device that resulted from this research was found to be more stable than conventional perovskite cells and, importantly, optimized for use in industry.

Perovskite/silicon cells under test at KAUST outdoor facility

The findings of KAUST Research Scientists Dr. Erkan Aydin and Dr. Thomas Allen, and colleagues in Professor Stefaan De Wolf's group, indicate that the temperature dependence of both the silicon and perovskite bandgaps'which follow opposing trends'shift the current-matching-optimization point away from that for two-terminal tandems under standard test conditions.

Oxford PV's Professor Henry Snaith recently stated that the Company's perovskite-based solar cells are scheduled to go on sale next year.

Professor Snaith said: "Perovskite PV has demonstrated its immense opportunity to transform solar energy generation... I am especially looking forward to the next 12 months and seeing our first commercial perovskite-silicon solar product on the market."

A team of scientists, led by Professors Hyunsik Im, Hyungsang Kim and Jungwon Kwak from Dongguk University and Asan Medical Center in Korea,have developed perovskite metal halide nanocrystals based hybrid materials with high quantum yields for efficient X-ray detection and high-resolution X-ray imaging.

Using the hybrid nanomaterial scintillators, they designed a scalable and cost-effective X-ray detector panel in liquid form. The hybrid nanomaterial scintillator works under X-ray irradiation typically employed in both diagnosis and treatment. More interestingly, the hybrid scintillator has a faster scintillation decay process over the conventional scintillators, which is beneficial for digital motion X-ray. The reported method and scintillation mechanism will be extended to enhance the quantum yield of various types of scintillators, enabling low-dose radiation detection in various fields including fundamental science and imaging.

Poland-based PSC developer Saule Technologies recently announced a partnership with Columbus Energy, the largest service provider on the market of photovoltaic installations in Poland.

As part of this partnership, Saule Technologies received a €10 Million investment from Columbus Energy.

University of North Texas professor Anupama Kaul has received a $474,000 grant from the Office of Naval Research under the Department of Defense to develop new perovskite-based solar cell technology.

Kaul, who directs the Nanoscale Materials and Devices Lab and the PACCAR Technology Institute, intends to utilize perovskite materials that are extremely efficient at absorbing incoming light. Many perovskites used in solar cell research are made with solutions, and yet, remarkably, the solution processed materials are still highly absorbing to incoming light. The main advantage of solution processing is that it greatly reduces manufacturing costs of solar cells compared to the sophisticated and expensive infrastructure needed to make them with crystalline materials.

South Korea's Ministry of Trade, Industry and Energy (MOTIE) recently released a new roadmap for the domestic solar module industry that puts a strong focus on solar applications.

According to the document, domestic solar manufacturers and research institutes expect tandem solar cell technology based on silicon and perovskite to be the most promising candidates for PV products of the next generation. The Korean semiconductor and display industries, according to the MOTIE, may play a decisive role in this transition by providing its expertise in silicon product and thin film development.