Robust Nanofiber Films Prepared by Electro-Microfluidic Spinning for Flexible Highly Stable Quantum-Dot Displays

Quantum dot (QD)-based liquid crystal displays (LCDs) are emerging as a new generation of LCDs due to their good performance. However, the QD fluorescent materials in LCDs are vulnerable to water and high temperatures, severely limiting their practical and long-term use. Here, flexible and ultrastable QD-based color-converting films for LCD backlights are fabricated using robust poly(styrene-methyl-methacrylate-acrylic acid) (poly(St-MMA-AA)) nanoparticle/polyamide 66 nanofiber (NPs@PA66) film with unique fiber–particle–fiber microstructure as protective substrate. Through an emerging strategy called electro-microfluidic spinning technology (EMST), the nanofiber film not only exhibits excellent flexibility but also remarkably improves the mechanical property via the in situ particle-mediated enhancement mechanism. An LCD backlight using the NPs@PA66 nanofiber film as QD loading substrate shows a wide color gamut of 116% and long-term fluorescence stability under high temperature of 200 °C. More importantly, the fluorescence lifetime of NPs@PA66/QDs backlight reaches up to ≈64500 h, ≈22 times higher than that using encapsulated sandwiched polyethylene terephthalate (PET) QD film. These findings offer a promising method toward high-strength nanofiber manufacturing, high-stability flexible electronics and optoelectronic display devices.