Scientists obtain 29.9% effectivity for four-junction perovskite-CSI tandem photo voltaic cell

November 20, 2023 Emiliano Bellini

A global analysis crew has fabricated a four-junction (4T) tandem photo voltaic cell primarily based on perovskite and copper/indium/selenium (CIS) thin-film with an influence conversion effectivity of as much as 29.9%.

The scientists stated they used halide salt methyldiammonium diiodide (MDADI) for floor defect passivation, which they stated lowered the open-circuit voltage loss within the system’s high cell primarily based on perovskite whereas enhancing the general tandem cell effectivity and near-infrared (NIR) transmittance.

The scientists grew the highest cell by a multi-stage co-evaporation course of. The system was primarily based on a substrate made from glass and indium tin oxide (ITO), a gap transport layer (HTL) made from nickel(II) oxide (NiOx), a perovskite absorber, a buckminsterfullerene (C₆₀) electron transport layer (ETL), a tin oxide (SnOx) layer, an ITO layer, and an ultrathin lithium fluoride (LiF) interlayer.

“We then differ the optical pathways inside the semi-transparent entrance cell to understand the management of the interference spectrum,” the crew defined. “By matching the optical interference with the AM 1.5 G irradiance spectrum, the perovskite entrance cell achieves excessive common NIR transmittance (ANT) of 81.5% and an effectivity of 21.8%.”

The lecturers additionally defined that the MDADI-treated movie can attain a a lot greater quasi-Fermi stage splitting (QFLS) in contrast with the one with out the therapy. “The pseudo current-voltage (J-V) plot reveals that the MDADI-treated movie reaches an implied open-circuit voltage of 1.29 V, whereas the untreated movie reaches only one.24 V, and this marks a distinction of round 50 mV.”

This high cell was then mixed in a tandem system with a backside cell made with a glass substrate coated with molybdenum (Mo), a CIS absorber, a cadmium sulfide (CdS) buffer layer, and a window layer of zinc oxide (i-ZnO). This system has an effectivity of 17.3%, an open-circuit voltage of 0.60 V, a short-circuit present density of 39.7 mA/cm2, and a fill issue of 72.9%.

Examined underneath customary illumination circumstances, the perovskite-CIS tandem cell achieved an effectivity of 29.9%, which the group stated is the best effectivity ever recorded for a perovskite-CIS tandem photo voltaic cell on the analysis stage so far.

The scientists described the system within the research “29.9%-efficient, commercially viable perovskite/CuInSe₂ thin-film tandem photo voltaic cells,” which was lately revealed in Joule. “These findings point out the huge alternatives for all thin-film-based perovskite/CIS tandem cells in various functions and pave the best way for his or her commercialization,” they stated. “The mix of superior efficiency and cost-effectiveness makes them a pretty prospect for the photo voltaic trade.”

The analysis group included teachers from the Nationwide College of Singapore, Switzerland’s Federal Laboratories for Supplies Science and Know-how (EMPA), and Germany’s Forschungszentrum Jülich.