Photochromic clock reaction of anthraquinone in supramolecular gel and its application to spatiotemporal patterning

Abstract

Nonlinear chemical dynamics observed in clock and oscillating reactions are crucial for understanding non-equilibrium systems and designing sophisticated chemical systems and functional materials. Here, we report anthraquinone-based photochromic gel materials showing a clock reaction-like behavior in the color and fluorescence changes. This unique coloration dynamics results from competition between the photoreduction reaction and inhibition of the reaction by molecular oxygen, which is regulated in the supramolecular gel medium. The induction period until coloration is tunable by the dissolved oxygen concentration and the irradiated light intensity. Spatiotemporal photopatterning based on the photochromic clock behavior was also demonstrated for applications in encryption technologies and display devices.