Optics Express · 2021 · 14 citations · 29 references
Large scale ordered Au nanoarrays are fabricated by nanosphere lithography technique. The photoluminescence improvement of CsPbBr<sub>3-x</sub>I<sub>x</sub> nanocrystals by more than three times is realized in the CsPbBr<sub>3-x</sub>I<sub>x</sub> nanocrystal/Au nanoarray/Si structure. Time-resolved photoluminescence decay curves indicate that the lifetime is decreased by introducing the Au nanoarrays, which results in a increasing radiation recombination rate. The reflection spectra with two major valleys (the dip in the curve) located at ∼325 nm and 545 nm of Au nanoarray/Si structure, which illustrates two plasmonic resonance absorption peaks of the Au nanoarrays. The enhancement of photoluminescence is ascribed to a well match between the excitation/emission of CsPbBr<sub>3-x</sub>I<sub>x</sub> nanocrystals and localized surface plasmon/gap plasmon resonance absorption of the ordered Au nanoarrays, as also revealed from the finite-difference time-domain simulation analysis. Our work offers an effective strategy to improve the fluorescence of perovskite nanocrystals and provide the potential for further applications.
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