Customizable High-Contrast Optical Responses: Dual Photosensitive Colors for Smart Textiles

Abstract

Smart textiles demonstrating optical responses to external light stimuli hold great promise as functional materials with a wide range of applications in personalized decoration and information visualization. The incorporation of high-contrast, vivid, and real-time optical signals, such as color change or fluorescence emission, to indicate light on/off states is both crucial and challenging. In this study, we have developed a dual output photosensitive dye system possessing photochromic and photofluorescent properties, which was successfully applied to the dyeing and finishing processes of cotton fabrics. The design and fabrication of this dye system were based on the unique photoinduced proton transfer (PPT) principle exhibited by the water-soluble spiropyran (trans-MCH) molecule. The dual output response relies on the open-/closed-loop mechanism, wherein light regulates the trans-MCH molecule. Upon excitation by UV or visible light, the dye system and dyed fabrics display significant color changes and fluorescence switching in a real-time and highly reversible manner. Moreover, diverse photosensitive color systems can be tailored by direct blending with commercially available water-soluble dyes. By integrating high-contrast dual optical outputs into this scalable, versatile, and reversible dye system, we envisage the development and design of smart textiles capable of producing high-end products.

Photocycloaddition of Zero-Dimensional Metal Halide Hybrids with Reversible Photochromism

“…As shown in Figures 2b and S8, the signal of 4.16 ppm is assigned to methyl protons (H a ), while the peaks of 8.66 (H b ) and 7.99 ppm (H c ) derive from the pyridine ring. The peaks at 6.96 (H d ) and 7.91 ppm (H e ) are attributed to olefinic protons, and the pyrrole ring shows four signals located at 6.53 (H f ), 6.91 (H g ), 7.27 (H h ), and 11.37 (H i ), respectively. Upon 450 nm irradiation for 2 min, these signals of L in 1 disappear along with the emergence of distinct signals from L photodimers in 1a (Figures 2b and S9), indicating the rapid and complete transformation.…”

“…Reversible photochromic materials are of strong interest for optoelectronic devices, optical data storage, and encryption technologies. − Such materials usually display distinct colors in response to external photochemical stimuli via reversible isomerization, cyclization, or cycloaddition reactions during which molecular structures with different geometry, conjugations and optical features are achieved. ,− Nonetheless, most developed photoswitchable organic molecules occur exclusively in solution with the presence of catalyst, greatly hindering their applications in solid phase. ,− …”