New approach to stabilize perovskite material may yield improved solar cells

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 CsPbI3, 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.

Research team advanced toward nontoxic perovskite solar cells

A team of scientists at Washington University in St. Louis has found what may be a more stable, less toxic semiconductor for solar applications using a novel double perovskite oxide, discovered through data analytics and quantum-mechanical calculations.

An atomic model of KBaTeBiO6 (left), scanning transmission electron micrograph showing the atomic structure of KBaTeBiO6, along with snapshot of the synthesized powder (right). Credit: WUSTLAn atomic model of KBaTeBiO6 (left), scanning transmission electron micrograph showing the atomic structure of KBaTeBiO6, along with snapshot of the synthesized powder (right). Credit: WUSTL

Rohan Mishra, assistant professor of mechanical engineering & materials science in the McKelvey School of Engineering, led an interdisciplinary, international team that discovered the new semiconductor, made up of potassium, barium, tellurium, bismuth and oxygen (KBaTeBiO6). The lead-free double perovskite oxide was one of an initial 30,000 potential bismuth-based oxides. Of those 30,000, only about 25 were known compounds.

New approach to stabilize pervoskites may push PSCs forward

Researchers at KU Leuven have explained how a promising type of perovskites can be stabilized. The team has developed a process in which the crystals turn black, enabling them to absorb sunlight. This is said to be necessary in order to use them in solar panels.

"Silicon forms a very strong, rigid crystal. If you press on it, it won't change its shape. On the other hand, perovskites are much softer and more malleable," explains Dr. Julian Steele of the KU Leuven Centre for Membrane Separations, Adsorption, Catalysis, and Spectroscopy for Sustainable Solutions (cMACS). "We can stabilize them under various lab conditions, but at room temperature, the black perovskite atoms really want to reshuffle, change structure, and ultimately turn the crystal yellow".

Researchers encourage perovskite crystallization to create high-performance light-emitting diodes

Scientists at Linköping University (LiU), along with colleagues from China, have shown how to achieve efficient perovskite light-emitting diodes (LEDs). The researchers provide guidelines on fabricating high-quality perovskite light emitters, and consequently high-efficiency perovskite LEDs.

Interlayers help perovskite crystallisation for high-performance light-emitting diodes imageDifferent metal oxide layers affect the properties of the thin perovskite films. Credit: Charlotte Perhammar

The halide perovskites can be easily prepared by low-cost solution processing from precursor solution comprising metal halides and organic halides. The resulting perovskites reportedly possess excellent optical and electrical properties, making them promising candidates for various kinds of optoelectronic devices, such as solar cells, LEDs and photodetectors.

Perovskite solar cells' behavior under real-world conditions is tested - in the lab

Researchers at the lab of Anders Hagfeldt at EPFL, working with colleagues at the lab of Michael Grätzel, brought real-world conditions into the controlled environment of the lab. Using data from a weather station near Lausanne (Switzerland), they reproduced the real-world temperature and irradiance profiles from specific days during the course of the year, to test PSCs in real-world conditions.

PSCs tested for real world conditions in the lab image

With this approach, the scientists were able to quantify the energy yield of the devices under realistic conditions. “This is what ultimately counts for the real-world application of solar cells," says Dr. Wolfgang Tress from EPFL.