Synergistic defect passivation and energy band reconstruction via LiH ₂ PO ₄ additive for efficient inverted perovskite solar cells

not only promotes highly (100)-textured grain growth and passivates deep-level defects but also induces a global energy band reconstruction. By correlating x-ray photoelectron spectroscopies and ultraviolet photoelectron spectroscopies, we disclose that the anomalous, simultaneous increase in core-level binding energies originates from a Fermi-level-driven rigid band shift coupled with the formation of a robust interfacial dipole. This dual-action mechanism effectively suppresses non-radiative recombination and eliminates charge extraction barrier. Consequently, the optimized inverted PSCs achieve a champion power conversion efficiency of 24.11%, along with enhanced open-circuit voltage, fill factor, and long-term environmental stability.