Water-stable, biocompatible, and highly luminescent perovskite nanocrystals-embedded fiber-based paper for anti-counterfeiting applications

Abstract

In this study, we present a promising and facile approach toward the fabrication of non-toxic, water-stable, and eco-friendly luminescent fiber paper composed of polycaprolactone (PCL) polymer and CsPbBr3@SiO2 core–shell perovskite nanocrystals. PCL-perovskite fiber paper was fabricated using a conventional electrospinning process. Transmission electron microscopy (TEM) clearly revealed incorporation of CsPbBr3@SiO2 nanocrystals in the fibers, while scanning electron microscopy (SEM) demonstrated that incorporation of CsPbBr3@SiO2 nanocrystals did not affect the surface and diameter of the PCL-perovskite fibers. In addition, thermogravimetric analysis (TGA) and contact angle measurements have demonstrated that the PCL-perovskite fibers exhibit excellent thermal and water stability. The fabricated PCL-perovskite fiber paper exhibited a bright green emission centered at 520 nm upon excitation by ultra-violet (UV) light (374 nm). We have demonstrated that fluorescent PCL-perovskite fiber paper is a promising candidate for anti-counterfeiting applications because various patterns can be printed on the paper, which only become visible after exposure to UV light at 365 nm. Cell proliferation tests revealed that the PCL-perovskite fibers are cytocompatibility. Consequently, they may be suitable for biocompatible anti-counterfeiting. The present study reveals that PCL-perovskite fibers may pave way toward next generation biomedical probe and anti-counterfeiting applications. Graphical Abstract

Thermally Induced Reversible Fluorochromism by Self-Trapped Excitonic Emission in a Two-Dimensional Hybrid Copper(I)-Halide Single Crystal

“…We explored the potential PL applications of BzCuI. Fine powders of BzCuI blended with silicon oil as a binder have the potential to develop anticounterfeiting ink for generating multiple encryption effects. − Utilizing a simple screen-printing technique, a silicon oil-BzCuI blend was printed onto Whatman filter paper and developed (Figure S20a,b). Under normal lighting conditions, the screen-printed information was indiscernible to the human eye.…”

Surface coating induced room-temperature phosphorescence in flexible organic single crystals

“…A majority of the recent examples of luminescent anti-counterfeiting materials are made of polymers, perovskites or lanthanide-based materials. 59–62 The practical utility of these materials is limited because of their potential toxicity or low processability. Owing to their efficient optical waveguiding features, RTP and long lifetimes, we envisaged that the coated crystals ( 5@1 ) would be ideal for anti-counterfeiting applications.…”

Effect of Specific Surface Area and Hydrophobicity of Electrospun Nanofibers on the Sustained Release Performance of Diclofenac Sodium

“…DS, PLA, and PCL exhibit distinct absorbances when analyzed using a UV–vis spectrophotometer. − This method may be used to analyze the composition and release of the material in vitro. PLA and PCL are not soluble in water.…”