Erasable Photopatterning of Stilbene-Based Metal-Organic Framework Films

The development of photosensitive materials for erasable photopatterning is of significant interest in anti-counterfeiting and information storage applications. Herein two kinds of stilbene-based metal-organic framework (MOF) films with layer by layer method for studying photopatterning is reported. The resulting 2D Zn-2(sdc)(2) MOF film (sdc = 4,4 '-stilbenedicarboxylate) exhibits excellent photosensitive features with a very short photoconversion time (<35 s) while the 3D MOF Zn4O(sdc)(6) film does not have the property due to the fact that only parallel and short distance arrangement of olefin groups in the adjacent MOF layers can trigger [2+2] photocycloaddition. Furthermore, the Zn-2(sdc)(2) film indicates obvious reversible fluorescent photoswitch behavior between yellow and blue fluorescence emission, which can achieve high-efficient, erasable photopatterning with various sizes (ca. 20 microns to decimeter). This study not only develops a new kind of photosensitive crystalline network film but also provides erasable photopatterning from macroscopic to microscopic in optical applications.