Enhanced photoluminescence of CsPbBr${}_3$ quantum dots by localized surface plasmon

In this paper, we report a new method to fabricate the all-inorganic perovskites CsPbBr${}_3$ quantum dots using cesium trifluoroacetate (CsTFA) as the cesium source instead of cesium bromide (CsBr). Al/CsPbBr${}_3$ quantum dots film layers are fabricated by thermal deposition and spin-coating techniques. It is found that photoluminescence intensity of Al/CsPbBr${}_3$ quantum dots film exhibits 5.54-fold enhancement compared with pristine CsPbBr${}_3$ quantum dots film. Time-resolved photoluminescence decay curves show that the PL lifetime of CsPbBr${}_3$ quantum dots film decreases from 2.11 to 1.61 ns after combining with Al film. The cross-sectional electric field distribution of perovskite QDs nanocube on Al/glass substrate was calculated by finite element method. The finite element method simulation indicates that Al film arouse a localized surface plasmon resonance around 520 nm, which enhances the PL emission intensity of CsPbBr${}_3$ quantum dots film.