Carbazole-based highly solid-state emissive fluorene derivatives with various mechanochromic fluorescence characteristics. (June 2020)

• Record Type: Journal Article
• Authors: Tan, Shuai; Yin, Ya; Chen, Wenzhuo; Chen, Zhao; Tian, Wei; Pu, Shouzhi
• Is Part Of: Dyes and pigments. Volume 177(2020)
• Publication Date: 2020-06
• Subjects: Carbazole -- Fluorene -- Various fluorescence -- Aggregation-induced emission -- Mechanofluorochromism -- Morphology conversion; Dyes and dyeing -- Periodicals; Pigments -- Periodicals; 667.2
• DOI: 10.1016/j.dyepig.2020.108302
• Languages: English
• ISSNs: 0143-7208

Abstract

Abstract: Four carbazole-based fluorene derivatives 1 –4 have been successfully prepared. All these compounds showed highly solid-state emissive feature with various fluorescence. The aggregation-induced emission effect of compound 1 was investigated by the systematic research of photoluminescence spectroscopy, and the results indicated that luminogen 1 displayed obvious aggregation-induced yellow light-emitting phenomenon. In addition, the solid-state emission behaviors of these fluorescent molecules could be tuned by mechanical force. More specifically, luminogens 1 and 2 showed reversible mechanochromic fluorescence conversion between blue-green and yellowish brown emission colors, luminogens 3 and 4 exhibited reversible mechanochromic fluorescence conversion involving color changes from green or yellow to yellowish brown. Furthermore, the repeatabilities of their mechanofluorochromism phenomena were excellent. The powder XRD results confirmed that the morphology conversion between crystalline and amorphous phases was responsible for the mechanofluorochromic characteristics of 1 –4 . This work provides valuable reference for the exploitation of high-contrast mechanochromism materials. Graphical abstract: Four carbazole-based fluorene derivatives were prepared. These compounds showed color-tunable highly aggregative-state fluorescence. Furthermore, the emission behaviors of these luminogens could be tuned by mechanical force. Image 1 Highlights: Four carbazole-based fluorene derivatives were synthesized. All these compounds showed highly solid-state emissive feature with various fluorescence. Luminogen 1 exhibited obvious aggregation-induced emission behavior. These luminogens exhibited highly reversible mechanofluorochromic characteristics. The repeatabilities of mechanofluorochromic phenomena of these luminogens were good.