Multi‐Functional PEDOT:PSS as the Efficient Perovskite Solar Cells

Poly(3,4‐ethylenedioxythiophene) (PEDOT), particularly in its complex form with poly(styrene sulfonate) (PEDOT:PSS), stands out as a prominent example of an organic conductor. Renowned for its exceptional conductivity, substantial light transmissibility, water processability, and remarkable flexibility, PEDOT:PSS has earned its reputation as a leading conductive polymer. This study explores the unique effects of two additives, Bisphenol A diglycidyl ether (DGEBA) and Dimethyl sulfoxide (DMSO), on the PSS component of PEDOT:PSS films are shown. Both additives induce grain size growth, while DGEBA makes the PEDOT:PSS layer hydrophobic, which acts as a passivation to protect the perovskite layer, which is vulnerable to moisture. The other additive, DMSO, separates the PSS groups, resulting in increased conductivity through the free movement of holes. With these multi‐modified p‐type PEDOT:PSS, the ITO/M‐PEDOT:PSS/Perovskite/PCBM/Ag structured reverse structure solar cell has improved the power conversion efficiency (PCE) from 15.28% to 17.80% compared to the control cell with conventional PEDOT:PSS. It also maintains 90% for 500 h at 60 °C and 300 h at 1 sun illuminating conditions. This study investigates the effect of DGEBA and DMSO on PEDOT:PSS, and utilized in perovskite solar cells. DGEBA induces grain size growth and imparts hydrophobicity, protecting the perovskite layer from moisture. Meanwhile, DMSO enhances conductivity by separating PSS groups. The perovskite solar cell using modified PEDOT:PSS improves the power conversion efficiency with improved stability under heat and light‐induced conditions.