Taiwan's Academia Sinica announced that a group of its researchers has developed a two-terminal (2T) perovskite-silicon tandem solar cell with a power conversion efficiency of 31.5%.

“In the future, the research team will further optimize the manufacturing process, enlarge the cell area, improve the stability of the stacked components, and develop a manufacturing method that is more suitable for mass production,” the research institute said in a statement. “We achieved a high efficiency by reducing interface losses.”

The research group utilized an unspecified heterojunction (HJT) crystalline solar cell technology for the bottom device.

Furthermore, it used a top perovskite solar cell built with a substrate made of indium tin oxide (ITO), a hole transport layer (HTL) made of nickel(II) oxide (NiOx) and phosphonic acid called methyl-substituted carbazole (Me-4PACz), a perovskite absorber, a buckminsterfullerene (C60) electron transport layer (ETL), a tin oxide (SnOx) buffer layer, a transparent back contact made of indium zinc oxide (IZO), a silver (Ag) metal contact, and an anti-reflective coating based on magnesium fluoride (MgF2).

“We will continue to work closely with domestic academic research institutions and manufacturers to jointly develop this cell technology,” the research team, without revealing more technical details on the novel cell concept.

Chinese manufacturer Longi holds the world record for perovskite-tandem solar cell efficiency, achieving 34.6% efficiency in September. In 2023, Saudi Arabia’s King Abdullah University of Science and Technology (KAUST) announced a perovskite-silicon tandem device with an efficiency of 33.7%.

Researchers from Germany’s Fraunhofer Institute for Solar Energy Systems (Fraunhofer ISE) recently said that the practical power conversion efficiency potential of perovskite-silicon tandem solar cells could reach up to 39.5%. Researchers said exceeding this efficiency threshold requires a change in cell architecture, replacing buckminsterfullerene (C60) with a more transparent electron transport layer, and finding more transparent alternatives to indium tin oxide (ITO) layers.

by pv magazine