Electrostatically Enhanced Self‐Assembled Monolayers Anchoring for Scalable and Stable Inverted Perovskite Solar Cells

Self-assembled monolayers (SAMs) have substantially advanced the efficiency of inverted perovskite solar cells (PSCs), yet weak interfacial adhesion to transparent conductive oxide (TCO) substrates and perovskite compromises both scalability and thermal stability. Here, an electrostatically enhanced anchoring strategy (EEAS) is presented using sulfadiazine (SDZ) molecules to deprotonate phosphonic acid groups in SAMs, generating phosphate anions that strengthen electrostatic interactions with the positively charged TCO substrates. The protonated SDZ species concurrently establish strong coordination interactions with the buried perovskite interface. This approach enables the formation of uniform and robust buried interfaces while improving perovskite crystallinity and facilitating charge extraction. The resulting PSCs achieve a certified efficiency of 26.23% (steady-state 25.42%) over 1 cm² areas. This EEAS is scalable, enabling 20.7-cm² modules with a PCE of 24.72%. The devices demonstrate exceptional operational stability, retaining over 94% of their initial efficiency after 1000 h of continuous illumination at 65 °C (ISOS-L-2).