The Perovskite-Info newsletter (February 15, 2022)

Los Alamos National Laboratory researchers and their collaborators have examined the performance properties of two-dimensional perovskites in conditions representative of a device structure, finding those structures can be as efficient as their three-dimensional counterparts.

“We discovered that intrinsic to this material, there are some shallow defects or ‘trap states’ that can help the charge transport over a long distance,” said Wanyi Nie, researcher with the Center for Integrated Nanotechnologies group at Los Alamos National Laboratory. “The travel distance is slightly lower than three-dimensional perovskites, but is much greater than what people believed in a typical 2D quantum-confined system. So this is a critical finding that two-dimensional perovskites can be efficient as three-dimensional perovskites.”

Scientists at the Karlsruhe Institute of Technology (KIT) and SUNOVATION Produktion have investigated the loss of efficiency caused by coloring the glass substrate, as part of their research on perovskite cells printed on glass.

PSCs and modules colored with inkjet-printed pigments in various bright colors and color patterns. Image from RRL Solar

The color was applied by inkjet printing, with first a white layer and then another color layer being deposited on top. The method is not new and has been used for years (by module manufacturer Sunovation Produktion GmbH of Elsenfeld, Germany, that was part of this research, and also by others) for colored modules with silicon cells. However, silicon cells absorb light in a different wavelength range than perovskite cells, which is why the same color application results in different final efficiencies.