Work

Decoding Fluorine Peripheral Substitution Impact in Zinc Phthalocyanines for Perovskite Solar Cells

Year: 2025

Type: article

Abstract: We designed six zinc phthalocyanine derivatives (ZnPc‐1–ZnPc‐6) as molecular semiconductors. By adjusting peripheral substituents with differing electron‐donating and ‐withdrawing properties (–C(CH 3 ) 3 , –O(CH 2 )CF 3 , –CF 3 ), we rationalized solubility, energy levels, and molecular arrangement to influence interfacial charge dynamics and thus device performance. Among the derivatives, ZnPc‐2 with three tert ‐butyl groups and a trifluoroethoxy provides favorable energy level alignment, better thin film coverage, and high conductivity suited to be used as hole‐selective materials. When integrated into n–i–p architecture perovskite solar cells, it measures a power conversion efficiency approaches that of Spiro‐OMeTAD under our lab conditions. ZnPc‐2 showed ambient operational stability, maintaining around 80% of its initial J MPP over 24 h without encapsulation. Our combined theoretical and experimental assessment revealed detailed electro‐optical properties to substantiate the influence of molecule design on the device performance. Specifically, three tert ‐butyl groups with a trifluoroethoxy arm outperform, evidencing molecular design as a strategy to modulate properties.

Source: ChemSusChem

DOI: 10.1002/cssc.202502045