Indepth Studies on Working Mechanism of Plasmon-Enhanced Inverted Perovskite Solar Cells Incorporated with Ag@SiO₂ Core-Shell Nanocubes

Noble metal nanoparticles-induced localized surface plasmon resonance as a useful approach has been widely used in solar cells including perovskite solar cells (PSCs) to improve their light-harvesting. Herein, we synthesize Ag SiO₂ core-shell nanocubes and investigate their application in CH₃NH₃PbI₃-based PSCs due to both the large local EM field induced by the nanocube with sharp corners and the effective avoidance of exciton/carrier recombination at the surfaces of Ag nanocubes via covering a 5 nm ultrathin SiO₂ shell. Incorporating an appropriate concentration of Ag SiO₂ nanocubes into the CH₃NH₃PbI₃ PSCs realizes a best-performing efficiency of 17.22% with an enhancement factor of 18.1%. Indepth studies on the plasmon-enhanced working mechanism of AgSiO₂ nanocubes with UV-vis absorption spectra, steady-state and time-resolved transient photoluminescence, and electrochemical impedance spectroscopy characterizations eventually demonstrate both the increasing light harvesting and the improving charge transportation and extraction contribute to better performances of PSCs.