Constructing on-demand single/multi-color transitioning fabrics with photocatalysis/photothermal-armed deficient semiconductors

On-demand color switching systems that utilize synchronized semiconductor-catalyzed reduction and photothermal-accelerated oxidation in liquid/solid are highly appealing. Herein, on-demand single/multi-color switching fabrics have been constructed by using defective SnO2:Sb-based color switching systems. SnO2:Sb nanocrystals with the suitable doping concentration accord lattices with abundant free electrons, conferring high photocatalytic and photothermal performances. A well-crafted set of dual light-responsive semiconductor-catalyzed systems with rapid color change can be attained via the homogenous mixture of SnO2:Sb with suitable redox dyes to produce single-color (RGB (red, green, blue)) and multi-color transitioning (purple and green) systems. The illumination of these systems by 450 nm light triggers rapid photocatalytic discoloration, while irradiation by 980 nm light confers the photothermal effect that accelerates recoloration in air. Besides, the inks can be extended to rewritable fabrics by embedding the nanocrystals and redox dyes into hydroxyethyl cellulose (as the polymer matrix) and then coating on hydrophobic cotton fabrics to produce photo-switchable fabrics with excellent single/multi-color response. By exploiting the dual light interactions with the semiconductor-mediated systems, various images/letters can be remotely printed and erased on the rewritable fabrics which show promise for potential applications as information storage media and visual sensors. Importantly, the present rewritable fabric shows good stability and reversibility. The present work provides insights into the development of novel color-switching materials.