Monodisperse Regulation of Self‐Assembled Monolayer Via Dipole Molecules for Efficient Perovskite Solar Cells

Abstract The application of self‐assembled monolayers (SAMs) significantly drives the enhancement in the efficiency of perovskite solar cell (PSC). However, the transition mechanism of SAM molecules from colloidal solutions to films remains unclear. Herein, we systematically investigate the SAM precursor solutions and the crystallization quality of the resulting SAM and perovskite films. Fibrous micelles of about 460 nm are found in the pristine SAMs solution, leading to nonuniform and low coverage distribution of films. Strong dipole molecules are employed to establish supramolecular interactions with SAMs, enabling the formation of highly monodisperse cubic micelles in solution (160 nm) and uniform SAM films. The contact at buried interface is determined by the balance between dipole moment and steric hindrance. Consequently, the regulated SAMs based inverted PSCs (0.09 cm 2 ) and mini‐module (aperture area of 14.40 cm 2 ) achieves efficiency of 26.58% (certificated 25.81%) and 22.95%, respectively. The optimized devices retain more than 96.30% of the initial efficiency for 5,100 h under the ISOS‐D‐1 condition with a linear fitting extrapolation to T 90 of 11,259 h and 98.30% efficiency for 2,660 h under the ISOS‐L‐2 condition. This work highlights the great potential of SAMs micelle regulation for achieving efficient and stable PSC.