Enhanced photoluminescence of CsPbBr 3-x I x nanocrystals via plasmonic Au nanoarrays

• Published in: Optics express Vol. 29; no. 22; p. 36988
• Main Authors: Wu, Yangqing, Han, Qiaoling, Wang, Mei, Juan, Fangying, Hou, Guozhi, Xun, Fan, Wei, Haoming, Xu, Jun, Cao, Bingqiang
• Format: Journal Article
• Language: English
• Published: 25.10.2021
• ISSN: 1094-4087; 1094-4087
• DOI: 10.1364/OE.443112

Large scale ordered Au nanoarrays are fabricated by nanosphere lithography technique. The photoluminescence improvement of CsPbBr 3-x I x nanocrystals by more than three times is realized in the CsPbBr 3-x I x 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 3-x I x 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.