Multiple Anti‐Counterfeiting Guarantees from a Simple Tetraphenylethylene Derivative – High‐Contrasted and Multi‐State Mechanochromism and Photochromism

• Published in: Angewandte Chemie International Edition Vol. 58; no. 49; pp. 17814 - 17819
• Main Authors: Huang, Guangxi, Xia, Qing, Huang, Wenbin, Tian, Jianwu, He, Zikai, Li, Bing Shi, Tang, Ben Zhong
• Format: Journal Article
• Language: English
• Published: WEINHEIM Wiley 02.12.2019; Wiley Subscription Services, Inc
• Edition: International ed. in English
• Subjects: aggregation induced emission; anti-counterfeiting; Chemistry; Chemistry, Multidisciplinary; Counterfeiting; Emission; Intermediates; Irradiation; mechanochromism; Molecular interactions; Photochromism; Physical Sciences; Science & Technology; Single crystals; tetraphenylethylene; Ultraviolet radiation; anti-counterfeiting; FLUORESCENT; LUMINESCENCE; photochromism; tetraphenylethylene; AGGREGATION-INDUCED EMISSION; aggregation induced emission; mechanochromism; CRYSTALS; MOLECULES
• ISSN: 1433-7851; 1521-3773
• DOI: 10.1002/anie.201910530

Herein the novel tetraphenylethylene (TPE) derivative 1 was designed with an integration of aggregation‐induced emission (AIE), multi‐state mechanochromism and self‐recovery photochromism. The molecule was susceptible to grinding, heating and vapor fuming and showed corresponding transition of its emission colors. The heated powder or single crystal of 1 exhibited reversible photochromism. After a short period of UV irradiation, it showed a bright red color, but recovered to its original white appearance within 1 min. The photochromism is due to the formation of photocyclization intermediates upon UV irradiation, while the eversible mechanochromism is attributed to the weak molecular interactions derived from head‐to‐tail stacking of the molecules. This reversible multi‐state, high‐contrasted and rapid responsive mechanochromic and photochromic property cooperatively provide double enhancement of a multimode guarantee in advanced anti‐counterfeiting. Forgery‐proof: A novel AIE molecule 1 is designed with high‐contrasted and multi‐state mechanochromic and photochromic properties. Based on these properties, 1 shows great potential for application in advanced multidimensional anti‐counterfeiting, which was demonstrated by fabrication of a model banknote.