Bulk Passivation of Perovskite Films With Phthalocyanine Derivative for Enhanced Perovskite Solar Cells Efficiency and Stability

Abstract Perovskite solar cells (PSCs) have emerged as a promising candidate for low‐cost and high‐efficiency photovoltaic solutions, poised to rival conventional photovoltaic technologies. Despite their potential, the path to commercialization is impeded by the significant defect state density present within the films. In this work, a phthalocyanine derivative, tetra‐2‐(benzyloxy)ethoxy substituted Zn(II) phthalocyanine (BE‐ZnPc), characterized by multiple binding sites, is introduced into the perovskite precursor solution. This innovative approach is designed to modulate the crystallization process of the perovskite and to passivate defects through a strategic doping mechanism. The BE‐ZnPc molecule, with its planar macrocyclic structure and electron‐donating attributes, engages effectively with the undercoordinated Pb2+ ions, thereby diminishing the defect density and enhancing the overall film quality. The resultant PSCs, optimized with BE‐ZnPc, have achieved power conversion efficiencies (PCE) as high as 26% (with a certified PCE of 26.05%), marking a significant milestone in PSC performance. Moreover, these devices maintain an impressive 92% of their initial PCE following 550 h of operation at the maximum power point. This study delineates a novel strategy for bolstering both the efficiency and durability of PSCs through the utilization of functional phthalocyanines, charting a new course for the advancement of PSC technology.