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 Ag@SiO2 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.