Perovskite Solar - Page 49

Researchers from Nanyang Technological University, Singapore (NTU Singapore) and the Institute of Materials Research and Engineering (IMRE) at the Agency for Science, Technology and Research (A*STAR) in Singapore have developed a method for capping materials based on non-toxic metals being used in the manufacture of perovskite solar cells.

(Left) A diagram showing the different layers of the perovskite solar cell capped with the zinc-based capping material fabricated by the researchers. (Right) The dotted green rectangle indicates the active region of the perovskite solar cell that captures sunlight and converts it to electricity. Image: NTU Singapore / Nature Energy

Perovskite solar cells are made of several layers of materials, including a perovskite layer that harvests light and a capping layer. The capping layer is coated onto the perovskite layer to protect the solar cell from environmental stresses such as heat and moisture and to boost the performance of the cell. To ensure that the capping layer is compatible with the underlying perovskite layer, researchers typically use an approach called the half precursor (HP) method to fabricate the capping layer. One of the precursor chemicals is first deposited on top of the perovskite layer which provides the other precursor. Through a process known as cation exchange reaction, the deposited precursor then reacts with lead ions present in the perovskite layer beneath to form a lead-based chemical compound that makes up the capping layer. As a result of the HP method, lead is also present in the protective capping layer. A method that enables non-toxic metals to be used in the capping layer could be a game-changer for perovskite solar cells.

Researchers from Eindhoven University of Technology and TNO at Holst Centre have developed a sensor that converts light into an electrical signal at an astonishing 200% efficiency – a seemingly impossible figure that was achieved through the exceptional nature of quantum physics.

SA schematic of the photodiode architecture

The team of scientists sees its invention potentially used in technology that monitors a person's vital signs (including heartbeat or respiration rate) from afar, without the need for anything to be inserted or even attached to the body.

Researchers from Korea's Institute for Basic Science (IBS), Chinese Academy of Sciences, the University of Rochester in the U.S, and The Australian National University have increased the photoresponsivity of a lead-halide perovskite for solar cell applications by 250%. They created a perovskite film with a plasmonic substrate made of hyperbolic metamaterial and characterized it with transition dipole orientation.

The team has considerably reduced electron recombination processes in lead-halide perovskites (LHPs) used for solar cell applications. Recombination 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.

Scientists from The University of Toledo, University of Washington, Northwestern University, University of Toronto and Empa–Swiss Federal Laboratories for Materials Science and Technology, have addressed a major challenge standing in the way of the commercialization of halide perovskite solar cells - their durability - by discovering an ingredient that enhances adhesion and mechanical toughness.

“Perovskite solar cells offer a route to lowering the cost of solar electricity given their high power conversion efficiencies and low manufacturing cost,” said Dr. Yanfa Yan, UToledo Distinguished University Professor of physics and a member of the UToledo Wright Center for Photovoltaics Innovation and Commercialization. “However, we needed to strengthen the emerging solar cell technology’s endurance during outdoor operation”. The technology needs to survive for decades outdoors in all kinds of weather and temperatures without corroding or breaking down.

QD Solar, a Canada-based venture developing tandem solar technologies, has announced 3rd party-validated efficiencies of their single junction perovskite cells. The 24% efficiency for spin-coated perovskites cells and the 23.2% efficiency for slot-die coated, manufacturing-ready, perovskite cells have been officially confirmed by MKS Instruments/Newport in Utah, USA.

“The silicon-dominated solar industry is suffering from eroding single digit profit margins for the past decade due to fierce worldwide competition. This industry has also suffered from stagnated solar efficiencies, due to fundamental limitations related to the inherit physics of silicon. This industry demands the next generation of bankable solar materials. Deploying low-cost perovskite-based solar will allow our customers, the solar panel manufacturers, to charge premium prices on high-efficiency panels and double their profit margins. That’s huge for the solar industry,” says Dan Shea, CEO of QD Solar.

Scientists from Saudi Arabia’s King Abdullah University of Science and Technology (KAUST) have reported the results of a one-year outdoor test for a tandem perovskite-silicon solar cell they developed in 2020. They have found that the device retained more than 80% of its initial efficiency during the testing period between April 2021 and April 2022.

The team's results are actual outdoor measurement over months and months, rather than testing done in a lab-controlled environment. The team is still conducting tests, aiming to focus on stability and reach  at least a two-decade operation goal.

Researchers from NREL, University of Wisconsin—Stout and Swift Solar have reported perovskite-based thermochromic windows that reduce energy load and carbon emission in buildings. The team calculated and fabricated a perovskite-based technology with excellent transition temperatures for building energy savings. 

The use of thermochromic windows in office buildings improves energy efficiency across all climate zones in the United States by modulating the temperature inside, leading to a massive savings, according to the research effort led by the U.S. Department of Energy’s National Renewable Energy Laboratory (NREL).

Researchers at University of Rome “Tor Vergata”'s CHOSE (Centre for Hybrid and Organic Solar Energy), Greatcell Italy, ISM-CNR and ENEA have studied a standard triple cation perovskite (∼1.58 eV) and wider bandgap perovskite (∼1.63 eV) with intention of finding a common strategy to build a robust device stable over time independently of the perovskite used.

The scientists used a combination of additives inside the perovskite ink: ionic liquid 1-Butyl-3 methylimidazolium tetrafluoroborate (BMIM-BF4), alkylamine ligands oleylamine (OAm) and benzylhydrazine hydrochloride (BHC). The recent work reveals that the combination of these additives helps to improve the efficiency and stability of the entire device, reaching a power conversion efficiency up to 21.3% and over 20% for both types of perovskite and stability beyond 1000 h under continuous light soaking.

Researchers from Georgia Institute of Technology, Argonne National Laboratory and Brookhaven National Laboratory have demonstrated that halide perovskite solar cells are less stable than previously thought. Their work reveals the thermal instability that happens within the cells’ interface layers, but also offers a path forward towards reliability and efficiency for halide perovskite solar technology.

The research could have significant implications for both academics and industry professionals working with perovskites in photovoltaics.

Researchers from Australia's Monash University, The Australian National University (ANU), Flinders University, The University of Sydney and Germany's Karlsruhe Institute of Technology have achieved a 30.3% efficiency with a perovskite and silicon tandem solar cell.

The team developed the highly efficient tandem cell, while also enhancing its operational stability. Their work builds on a previous record set by ANU researchers in 2020, and was funded by the Australian Renewable Energy Agency (ARENA).