Surface Plasmon Resonance Effect Enhanced CsPbBr3 Inverse Opals for High‐Performance Inorganic Perovskite Solar Cells

Abstract Although all‐inorganic CsPbBr 3 are considered an ideal candidate for inorganic perovskite solar cells (PSCs) owing to their outstanding thermal‐ and moisture‐resistance, it still suffers from unfavorable charge transfer process and limited light harvesting ability. Herein, CsPbBr 3 inverse opal (IO) films coupled with Au nanoparticles (NPs) are rationally designed, and PSCs based on Au‐CsPbBr 3 IO achieve a stabilized photoelectric conversion efficiency up to 8.08%. By selectively tuning IO pore diameter, the slow photon region of CsPbBr 3 IO and localized surface plasmon resonance (SPR) region from Au NPs can be modulated to be overlapped to enhance the performance of inorganic CsPbBr 3 PSCs. The synergetic effect devotes to light utilization and charge transfer process, resulting in an enhanced light absorption capability and suppressed recombination rate of photogenerated electron–hole pairs. The introduction of Au not only triggers SPR effect, but also enhances efficient separation/injection of charge carriers owing to the Schottky barriers. Furthermore, it is revealed that simultaneous effect from SPR and IO photon effect are conducive to reduce exciton binding energy, enhancing exciton dissociation efficiency and leading to significant increase in free carrier density. This work provides a rational strategy for plasmonic metal/semiconductor composite light‐absorber for high‐performance inorganic PSCs.