Fig. 1: Concept and preparation of self-growth of programmable 2D/3D-coupling responsive coating.
From: Self-growth of programmable 2D- and 3D-coupling responsive coating for anti-counterfeiting
a Anti-counterfeiting illustration of hand-drawn commemorative currency based fluorescence patterns (2D) and 3D structures. b Schematic diagram of the coupling of the 3D structure and color (2D) of a gecko. c Self-growth diagram of 2D/3D-coupling responsive coating and the corresponding structures of fluorescence dye, photo-induced reversible transformation of photochromic molecules and fluorescence resonance energy transfer (FRET) process (UV: 365 nm; Visible light (Vis.): 525 nm), polymer, crosslinker, dynamic interaction, reversible fluorescence switching and three-dimensional (3D) structure switching. Fluorescence switching depended on the photo-induced FRET process between fluorescence dyes and photochromic molecules. 3D structures switching depended on the thermo- and force-induced dynamic interaction to trigger the shape memory.
