High stability and spectral tunability of versatile manganese/europium/tellurium-doped double perovskite crystals toward flexible functional fabric and semiconductor devices.

Color-tunable manganese/europium/tellurium-doped halide perovskites are synthesized and can be used to post processing fibers for LEDs and anti-counterfeiting and detection materials. [Display omitted] • Color-tunable manganese/europium/tellurium-doped halide perovskites are synthesized. • Perovskites are composited with flexible fibers to prepare luminescent fibers. • The perovskite crystals can be used to fabricate light-emitting diode lamps. • Expanding the application of compound flexible fiber and perovskite. All-inorganic metal halide perovskites exhibit excellent optoelectronic properties, and cesium lead halide perovskites have been the most extensively studied perovskites. Despite their excellent performance, the toxicity of CsPbX 3 (X = halide) perovskites is a significant hurdle in the path of their widespread commercialization, posing challenges for large-scale applications. The lead-free characteristic and inherent air stability of Cs 2 NaBiX 6 render them promising alternatives to CsPbX 3 perovskites. Herein, we report the lead-free double perovskite crystals (PCs) derived from Cs 2 NaBiCl 6 incorporating doping with three distinct elements. This doping strategy effectively regulates the emission wavelength of Cs 2 NaBiCl 6 , with particular emphasis on Eu-doped and Te-doped Cs 2 NaBiCl 6 , which have been scarcely reported in previous studies. Light-emitting diodes (LEDs) have been fabricated by these perovskite crystals. The white LED was prepared by Mn-doped Cs 2 NaBiCl 6 with a high color rendering index (CRI) of 95.5. In addition, fiber paper, composed of aramid chopped fibers (ACFs) and polyphenylene sulfide (PPS), exhibits sustained fluorescence characteristics in different environments under an ultraviolet lamp when post-processed with perovskite. The photoluminescence quantum yield (PLQY) of flexible luminescent fibers prepared from Cs 2 (NaBi) 0.95 Mn 0.10 Cl 6 PCs and ACFs/PPS fibers can reach 18.27 %. This fluorescent fiber paper holds potential applications in fields such as fluorescent anti-counterfeiting and intelligent wearable devices. By irradiating with a specific wavelength of the laser, the damaged area of fiber textiles can be quickly detected based on changes in fluorescence intensity. The integration of luminescent crystals and fibers into functional fabrics opens avenues for utilization in high-performance textile testing and other domains. [ABSTRACT FROM AUTHOR]