Fluorination of Star‐Shaped Cyclopenta[2,1‐b;3,4‐b′]dithiophene Derivatives and Its Application as Hole‐Transporting Materials in Scalable Perovskite Solar Cell Fabrication by Bar Coating

Perovskite Solar Cells In article number 2300988, Lee, Hsieh, Lu, Lin, and co-workers synthesized three star-shaped cyclopentadithiophene derivatives, with or without fluorine atoms incorporated, and applied them as hole-transporting materials in the fully scalable fabrication of perovskite solar cells (PSCs) using the thermal-assisted bar-coating method. The PSCs fabricated from such films delivered a high power conversion efficiency of 18.49% on a large scale with encouraging long-term stability.