Resolving the Electro‐Mechanical Trade‐Off at the Buried Interface of Perovskite Solar Cells

ABSTRACT Carbazole‐based self‐assembled monolayers (SAMs) are essential in inverted perovskite solar cells (PSCs) due to superior electrical properties, yet their inherent rigidity imposes severe mechanical stress on the perovskite layer. Herein, we construct an interfacial architecture featuring discontinuous metal‐oxide islands to circumvent this fundamental electro‐mechanical trade‐off at the buried contact. Specifically, this discontinuous topography imparts macroscopic structural flexibility to the interface by functioning as localized strain‑relaxation zones, enabling strain‐relaxed perovskite films with reduced defect density. Meanwhile, the modified interface maintains unimpeded hole‐selective pathways and optimal energy level alignment. Consequently, the corresponding PSC yields a champion power conversion efficiency (PCE) of 26.92% (certified 26.60%) with enhanced long‐term stability. This strategy establishes a rational design principle for synergistic electro‐mechanical management, paving the way for high‐efficiency and stable photovoltaic devices.