Synergistic Interface Modulation of Hole Transport for Efficient, Stable Inverted Perovskite Solar Cells

ABSTRACT Inverted perovskite solar cells (PSCs) have achieved remarkable power conversion efficiencies exceeding 27%, largely due to the introduction of self‐assembled monolayers (SAMs) that facilitate efficient interfacial charge transport. However, the practical application of these high‐efficiency devices is hindered by the poor thermal and photostability of SAMs, which leads to desorption from the substrate. In this work, we demonstrate a synergistic interface modulation strategy to simultaneously enhance efficiency and stability: (1) optimizing the oxygen flux during NiO X magnetron sputtering to improve film conductivity while creating abundant surface hydroxyl groups for robust SAM anchoring; (2) molecular modification of MeO‐2PACz to F‐2PACz by substituting methoxy with fluorine groups, which strengthens interfacial dipole moment and passivates halide vacancies. The resulting devices achieve a champion power conversion efficiency (PCE) of 25.75%, representing a significant improvement over control devices (24.25%), with the fill factor increasing substantially from 81.50% to 84.39%. Importantly, this approach is robust to area upscaling, delivering 25.06% PCE for 1 cm 2 devices with a relative efficiency loss of only 3.11%. Stability tests under ISOS‐L‐3 conditions (maximum power point tracking, continuous 1‐sun illumination at 65°C and 50% RH) demonstrate outstanding operational stability, with the optimized devices retaining 92% of their initial performance after 1440 h.