Mingqiao Ge

In recent years, luminous coated fabrics based on SrAl₂O₄: Eu²⁺, Dy³⁺ luminescent materials have attracted more attention. However, due to the single emission color of SrAl₂O₄: Eu²⁺, Dy³⁺ luminescent materials, the application of prepared coated fabrics has certain liminations. Therefore, at present, there is a need to develop a kind of luminous coated fabric which has the capability of emitting multiple colors of light. In this work, fluorescent pigments and SrAl₂O₄: Eu²⁺, Dy³⁺ luminescent materials were added to a coating slurry and uniformly coated over a woven fabric substrate. The effects of adding fluorescent pigments on the spectral characteristics of luminous coated fabrics were evaluated. The blue fluorescent pigment causes a significant blue shift in the emission spectrum of the blue light-emitting coated fabric, whereas the emission spectra of the orange and red light-emitting coated fabrics exhibit a significant red shift. The yellow-green fluorescent pigments significantly affect the coated fabric. The emission spectrum shows no evident change and is similar to the emission spectrum of white (without any fluorescent pigment) luminescent coated fabric. The afterglow brightness of the colored luminous coated fabrics decreases exponentially with time. Adding blue fluorescent pigments has a greater impact on the brightness of the coated fabrics. The initial brightness is lower and the afterglow brightness loss is higher when using yellow-green fluorescence. The pigment has little effect on the brightness loss of coated fabrics, and the initial brightness of the coated fabric increases when adding yellow-green fluorescent pigments. Fluorescent pigments result in relatively low color purity for each colored coated fabric. However, the color rendering index is high, and the color rendering performance for the light source is excellent.

The large‐scale synthesis of calcium terephthalate (CaTP) and upcycling of poly(ethylene terephthalate) (PET) are performed simultaneously by reactive processing. In the one‐pot synthesis, a spindle‐like calcium trihydrate CaTP‐80 with good crystallinity is derived and separated from PET waste by calcium hydroxide and water. Characterization techniques including Fourier‐transform infrared spectroscopy (FTIR), NMR, X‐ray diffraction (XRD), and thermal gravimetric analysis (TGA) reveal that the produced CaTP‐80 with an average size of 18.8 µm is tunable in the structure after calcination. The resulting anhydrous CaTP‐350 with different bonding modes between Ca²⁺ and COO⁻ exhibits high purity and thermal stability. Furthermore, an accurate quantification method operated by UV–vis is applied to define the selectivity and yield of CaTP powder from the complex intermediates. The effects of temperature, time, and concentration parameters on the yield of CaTP in the purification process are investigated. Results reveal that the optimum conditions are achieved with 88.2% conversion of PET to CaTP, 95.9% selectivity, and 84.6% yield of the synthesized CaTP‐350. The study complements the purification, characterization, and quantification of PET‐derived CaTP powder, which exhibits a model for effective and sustainable upcycling of PET waste.

Smart fibers with reversible optical properties have received extensive attention due to their wide potential for application in human health monitoring and wearable devices. However, achieving multi-stimuli-responsive luminescent fibers via a facile manufacturing process is challenging. Herein, novel independent multi-stimuli-responsive luminescent fibers are successfully fabricated via a facile wet-spinning process. The color of the fibers responds to ultraviolet (UV) and heat independently and in combination. The fibers emit bright red light emission (λ_em = 627 nm) after excitation (λ_ex = 330 nm) which is attributed to Y₂O₂S:Eu³⁺,Mg²⁺,Ti⁴⁺ ceramics. The as-prepared fibers possess a tensile strength of around 9.39 MPa. The experimental results demonstrate that the multi-stimuli-responsive persistent luminescent fibers coupled with the facile preparation process make the multi-stimuli-responsive luminescent fibers a potential candidate for application in anti-counterfeiting and UV/heat detection devices.