Fine CsPbX3@PVDF-HFP/PS electrospun nanofibers with efficient emission and high stability toward multifunctional fluorescent sensor

CsPbX3 (X = Cl, Br, I) perovskite nanocrystals (NCs) are emerging as promising candidates for fluorescence sensors due to their superior optoelectronic properties. However, the poor stability restricts their practical applications in aqueous fluorescent detection. Herein, we report in-situ encapsulation of CsPbX3 NCs into uniform PVDF-HFP/PS polymer nanofibers with fine diameter of only 49.9 ± 2.2 nm by one-step electrospinning process. The as-fabricated CsPbX3@PVDF-HFP/PS nanofibers exhibit high photoluminescence quantum yield (PLQY) of 90%, tunable emission wavelength covering the whole visible range of 451.5–650.8 nm. Most importantly, the water stability of nanofiber membranes can be significantly improved by introducing the 1H,1H,2H,2H-perfluorodecyltrimethoxysilane (PFDTMS) as hydrophobic additives, in which their PL intensity can retain 88% initial value after water immersion for up to 100 days. The universality of this fabrication strategy for the stable nanofibers is demonstrated by utilizing different types of polymers and perfluorosilanes (PFSs). Taking advantage of excellent optical properties, fine diameter and high hydrophobicity of PFDTMS-modified CsPbBr3@PVDF-HFP/PS nanofibers, the detection for rhodamine 6G (R6G) and rhodamine B (RhB) in aqueous solution with maximum fluorescence resonance energy transfer (FRET) efficiency up to 80.9% and 69.7% are realized, respectively. Notably, these electrospun nanofiber membranes possess outstanding durability and recyclability, indicating their great potential in multifunctional photoelectric applications.