In Situ Fabrication of Superfine Perovskite Composite Nanofibers with Ultrahigh Stability by One-Step Electrospinning Toward White Light-Emitting Diode

All-inorganic CsPbX3 (X = Cl, Br, I) perovskite nanocrystals (NCs) are emerging as promising candidate materials for optoelectronic devices due to their splendid optical and electrical properties. However, the intrinsic instability greatly limits their practical application. Herein, a feasible strategy is proposed for fabricating highly stable and luminescent CsPbBr3@ PVDF-HFP/PS nanofibers by combining one-step electrospinning method with 1H,1H,2H,2H-perfluorodecyltrimethoxysilane (PFDTMS)-assisted post-treatment. The bright-emitting CsPbBr3 NCs can be effectively encapsulated within polymer nanofibers, which exhibit ultrafine diameter of only 88.1 +/- 2.8 nm and high photoluminescence quantum yield (PLQY) of 87.9% via rationally optimizing the electrospinning parameters, concentration of perovskite precursors and ligands. Most importantly, the superhydrophobic surface structures of nanofibers are formed by the hydrolysis and condensation of PFDTMS under moist environment. Benefiting from the double effective protection of polymer matrices and hydrophobic PFDTMS oligomers against moisture erosion, the CsPbBr3@PVDF-HFP/PS nanofibers present an obviously improved stability, which can retain 90% initial PL intensity after water immersion for 70 days. Furthermore, an efficient white light-emitting diode with wide color gamut covering 117% of National Television System Committee (NTSC) standard is successfully fabricated based on the composite nanofiber membranes, suggesting their promising prospect for solid-state lighting and display applications.

Automated summary

This study proposes a strategy for fabricating highly stable and luminescent all-inorganic CsPbBr3@PVDF-HFP/PS nanofibers. Bright-emitting CsPbBr3 nanocrystals were successfully encapsulated within the polymer nanofibers by optimizing the electrospinning parameters, perovskite precursors, and ligands. Additionally, the nanofibers' hydrophobic surface structure formed through the hydrolysis and condensation of PFDTMS under moist conditions. The CsPbBr3@PVDF-HFP/PS nanofibers demonstrated improved stability due to the double protection of the polymer matrices and hydrophobic PFDTMS oligomers.