A research group, led by Prof. HAN Keli from the Dalian Institute of Chemical Physics of the Chinese Academy of Sciences, recently revealed the luminescence enhancement mechanism of a series of new lead-free quadruple halide perovskite nanocrystals, and prepared high-performance photodetectors.

The researchers reported a series of quadruple perovskite colloidal nanocrystals with ordered vacancies. By alloying Cs₄MnBi₂Cl₁₂ nanocrystals, the fluorescence quantum yield could be increased by nearly 100 times.

A research team from the Okinawa Institute of Technology (OIST) in Japan has developed a mini perovskite solar module based on large‐area uniform and dense perovskite films with a thickness of more than one‐micrometer.

The scientists fabricated two modules, sized 5x5cm² and 10x10cm², with efficiencies of 14.55% and 10.25%, respectively, which reportedly rely on perovskite layers with high crystallinity, large grain sizes, and small surface roughness.

A research team at NUST MISIS and the University of Tor Vergata recently presented an improved structure of perovskite solar cells. The scientists modified perovskite-based solar cells using MXenes — thin two-dimensional titanium carbides with high electrical conductivity. The MXenes-based modified cells reportedly showed superior performance, with power conversion efficiency exceeding 19% (the reference demonstrated 17%) and improved stabilized power output with respect to reference devices.

“In this work, we demonstrate a useful role of MXenes doping both for the photoactive layer (perovskite) and for the electron transport layer (fullerenes) in the structure of solar cells based on nickel oxide,” said the co-author of the paper, a researcher from the NUST MISIS Laboratory for Advanced Solar Energy, post-graduate student Anastasia Yakusheva. “On the one hand, the addition of MXenes helps to align the energy levels at the perovskite/fullerene interface, and, on the other hand, it helps to control the concentration of defects in the thin-film device, and improves the collection of photocurrent.”

Hunt Perovskite Technologies (HPT) recently announced the publication of its scientific article, jointly written with Colorado School of Mines and the United States Department of Energy's National Renewable Energy Laboratory.

In the article, the scientists identify and analyze the importance of perovskite thin film stoichiometry to its durability and the possible mechanisms that lead to rapid degradation of certain perovskite materials designed for use in the manufacture of photovoltaic (PV) solar cells. Their results provide key insights into ways to improve the fundamental durability and stability of perovskite PV modules.

Researchers from the Shaanxi Normal University in China have designed a perovskite solar cell based on methylammonium lead iodide (MAPbI₃) through a dual passivation technique that simultaneously passivates trap defects in both the perovskite and electron transport layer (ETL) films.

“So far, most techniques for modifying perovskite solar cells focus on either the perovskite or electron transport layer,” the research group reported, noting that the ETL must have decent optical transmittance and high electron mobility to extract photo‐induced carriers and contribute to the solar cell efficiency.

Rice University scientists, in collaboration with a team from Los Alamos National Laboratory (LANL), have reported a technology that could dramatically reduce the cost of semiconductor electron sources, key components in various devices that range from night-vision goggles and low-light cameras to electron microscopes and particle accelerators.

Perovskite semiconductors (silver) treated with a layer of cesium (blue-green) could be tuned to emit free electrons (gray) over both visible and ultraviolet spectra (colored arrows), and a layer of cesium could regenerate degraded photocathodes.

Billions of dollars are spent each year on photocathode electron sources made from semiconductors containing rare elements like gallium, selenium, cadmium and tellurium. "This should be orders of magnitude lower in cost than what exists today in the market," said study co-corresponding author Aditya Mohite, a Rice materials scientist and chemical engineer. He said the halide perovskites have the potential to outperform existing semiconductor electron sources in several ways.

Researchers from North Carolina State University and the University of Texas have developed and demonstrated a new approach for designing photonic devices. The new method enabled the team to control the direction and polarization of light from thin-film LEDs, overcoming the widely known obstacles of beam shaping that arise from their Lambertian nature. Such LEDs with directional and polarized light emission could be useful for many photonic applications.

“This is a fundamentally new device architecture for photonic devices,” says Franky So, corresponding author of a paper describing the work and Professor of Materials Science and Engineering at NC State. “And we’ve demonstrated that, using our approach, directional and polarized emissions from an organic LED or a perovskite LED without external optical elements can be realized”.