Strong Electron‐Withdrawing Molecules Facilitating π–π Stacking and Charge Transfer Complexes at Buried Interface and Enabling an Inverted PSC with Open‐Circuit Voltage of 1.2 V

To improve the interfacial match between the hole transport layer (HTL) and perovskite active layer (PAL) in inverted perovskite solar cells (PSCs), a strong electron-withdrawing molecule 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4TCNQ) is introduced to bridge the self-assembled monolayers (SAMs) [2-(3,6-dimethoxy-9H-carbazol-9-yl)ethyl]phosphonic acid (MeO-2PACz) and PAL. F4TCNQ eliminates molecular voids in the SAMs via π-π stacking, forming charge-transfer complexes that homogenize interfacial potential and promote perovskite crystallization, increasing grain size from 0.53 to 0.88 µm. The cyano groups and fluorine atoms on F4TCNQ passivate Pb²⁺ and I^- defects through coordination and hydrogen bonding, suppressing ion migration and carrier nonradiative recombination. Meanwhile, p-type doping by F4TCNQ elevates the SAMs work function, reducing the hole extraction barrier by 0.12 eV and enhancing charge transfer driving force. Optimized devices achieve a champion power conversion efficiency of 25.91% with a high open-circuit voltage of 1.202 V, while retaining 91% efficiency after 1000 h of maximum power point tracking, attributed to stabilized ion dynamics and robust interfacial adhesion. This work demonstrates molecular bridging as a scalable strategy for high-performance photovoltaics.