The Perovskite-Info newsletter

Scientists at the Chemistry and Physics Institutes of the University of Campinas (UNICAMP) in the state of São Paulo, Brazil, in collaboration with scientists at the University of Michigan in the United States, have provides insights into the fundamental physics of perovskite quantum dots.

"We used coherent spectroscopy, which enabled us to analyze separately the behavior of the electrons in each nanomaterial in an ensemble of tens of billions of nanomaterials. The study is groundbreaking insofar as it combines a relatively new class of nanomaterials - perovskite - with an entirely novel detection technique," Lázaro Padilha Junior, principal investigator for the project on the Brazilian side, explained.

Researchers from The Hebrew University of Jerusalem and Ben-Gurion University of the Negev in Israel, have studied the two-step deposition of perovskites in mesoporous-carbon-based perovskite solar cells. The team studied the effect of the different deposition parameters on the PV performance and stability.

b) Schematic illustration of the two-step deposition process. The first stage includes dropping of the PbI2 þ PbBr2 solution, the second step includes dipping into the cation solution of FAI þ MABr. Image from article

The influence of the dipping time on the photovoltaic parameters was investigated using charge extraction and intensity-modulated photovoltage spectroscopy (IMVS) measurements. By modifying the perovskite precursors’ concentration and the dipping time, a PCE of 15% was achieved. The dipping time in the perovskite deposition of this solar cell structure is critical due to its thickness and mesoporous structure.

Researchers from the National Renewable Energy Laboratory (NREL) have found that restructuring the way perovskite solar cells are designed can boost their efficiency and increase their deployment in buildings. Their newly proposed architecture for the cells increases the area exposed to the sun by putting the metal contact layers side-by-side on the back of the cell.

Photo by Kevin Prince/NREL

“Taking the materials on top away means you are going to have a higher theoretical efficiency because your perovskite is absorbing more of the sun,” said Lance Wheeler, a NREL scientist .

A research team, led by Los Alamos National Laboratory, has designed a simple solution for fabricating stable perovskite solar cells that is said to overcome the key bottleneck to large-scale production and commercialization of perovskite solar cells.

A new dipping process using a sulfolane additive creates high-performing perovskite solar cells. Image: LANL

The Los Alamos team, in collaboration with researchers from National Taiwan University (NTU), invented a one-step spin coating method by introducing sulfolane as an additive in the perovskite precursor, or the liquid material that creates the perovskite crystal through a chemical reaction. As in other fabrication methods, that crystal is then deposited on a substrate.