Large-scale and continuous production of perovskite filament for wearable fluorescent textiles

Perovskite quantum dots demonstrate significant potential for application in flexible displays and wearable devices owing to their exceptional optoelectronic properties. However, the continuous, large-scale, and stable production of perovskite fluorescent fiber based structures, particularly filaments and yarns, remains a formidable challenge due to their inherent susceptibility to moisture and heat, which calls for an advancement of the current spinning technology. In this work, a two-nozzle electrospinning technique was proposed, and CsPbX3@polyacrylonitrile (PAN) (X = Cl, Br, I) perovskite luminescent filaments with exceptional stability and safety have been fabricated, meeting the requirements for knittable and wearable applications. These filaments demonstrate intense and narrow-band photoluminescence (with a photoluminescence quantum yield of 53.8 % and a full-width at half-maximum of 27 nm), as well as exceptional stability against water (>90 days), ultraviolet irradiation, high temperatures (85 degrees C), and acid-base corrosion (pH from 1.5 to 9). The filaments demonstrate minimal release of lead ions (1.997 %) with a cell viability rate of 97.725 %, suggesting low cytotoxicity. Furthermore, favorable mechanical properties of the individual filament of CsPbX3@PAN (including a tensile strength of 2.99 N which can be further enhanced to 14.37 N through twisting into yarns) make it suitable for seamless integration into weaving and knitting processes. All the merits of our samples present promising potential in multifunctional applications such as pattern displays, anti-counterfeiting measures, information encryption, and personalized design.