Rb_0.25Cs_0.75PbBr₃/ZnO Nanocomposites with Enhanced Nonlinear Absorption and Refraction Properties for Nonlinear Optical Devices

Nonlinear optical (NLO) properties and environmental stability are two important issues in the application of Rb 0.25 Cs 0.75 PbBr 3 /ZnO nanocomposites for NLO devices. We present an easy-to-operate and efficient approach to improving these two issues. The Rb 0.25 Cs 0.75 PbBr 3 /ZnO nanocomposites were synthesized by a hot injection method. The ZnO, Rb 0.25 Cs 0.75 PbBr 3 quantum dots (QDs) and Rb 0.25 Cs 0.75 PbBr 3 /ZnO nanocomposites were dispersed into methyl methacrylate (MMA) to fabricate the (ZnO) 4 /polymethyl methacrylate (PMMA), (Rb 0.25 Cs 0.75 PbBr 3 ) 4 /PMMA, and (Rb 0.25 Cs 0.75 PbBr 3 /ZnO) 4 /PMMA organic glasses (OGs). The nonlinear absorption (NLA) and nonlinear refraction (NLR) properties of the samples were investigated by using the open-aperture and closed-aperture Z-scan technique. The results showed that the NLO properties of the (Rb 0.25 Cs 0.75 PbBr 3 /ZnO) 4 /PMMA OG were significantly improved compared with those of (ZnO) 4 /PMMA and (Rb 0.25 Cs 0.75 PbBr 3 ) 4 /PMMA OGs, which can be attributed to the positive synergistic effects between ZnO and Rb 0.25 Cs 0.75 PbBr 3 QDs. Due to the protective effect of PMMA, the linear absorption properties of the (Rb 0.25 Cs 0.75 PbBr 3 /ZnO) 4 /PMMA OG showed little change after 28 days to 4 months. In general, the results demonstrate that Rb 0.25 Cs 0.75 PbBr 3 /ZnO nanocomposites have enormous application potential in NLO devices.