A multi-state fluorescent switch with multifunction of AIE, methanol-responsiveness, photochromism and mechanochromism. Issue 38 (5th September 2018)

• Record Type: Journal Article
• Authors: Huang, Lili; Qiu, Yixin; Wu, Chenyang; Ma, Zhiyong; Shen, Zhihao; Jia, Xinru
• Is Part Of: Journal of materials chemistry. Volume 6:Issue 38(2018)
• Page Start: 10250
• Page End: 10255
• Publication Date: 2018-09-05
• Subjects: Materials -- Periodicals; Chemistry, Analytic -- Periodicals; Optical materials -- Research -- Periodicals; Electronics -- Materials -- Research -- Periodicals; 543.0284
• DOI: 10.1039/c8tc03728k
• Languages: English
• ISSNs: 2050-7526

Abstract

Abstract : In this article, we report a newly designed molecule, RhTPE, synthesized by fusing rhodamine with TPE, which realizes both emission color change and on/off switching. Abstract : In this article, we report a newly designed molecule, RhTPE, synthesized by fusing rhodamine with TPE, which realizes both emission color change and on/off switching. Compared to most of the reported fluorescent switches, such a unique structure endowed RhTPE with the multifunction of AIE, methanol-responsiveness, photochromism and mechanochromism, owing to the dynamic ring opening–closing isomerization. RhTPE is acid-sensitive and can recover to the ring-closed form (OF) by base treatment. Both RhTPE and trifluoroacetic acid (TFA)-treated RhTPE display AIE properties. It is noteworthy that during the aggregation process of TFA-treated RhTPE, the cyan emission strengthens while the red emission disappears, due to the aggregation-induced ring-closing reaction. RhTPE shows selective responsiveness to methanol out of all the twelve screened solvents, probably owing to the low p K a value and high polarity of methanol. More interestingly, RhTPE demonstrates excitation wavelength-dependent photochromism in several different organic solvents, which is very rarely reported in rhodamine systems. In the solid state, RhTPE has three well-distinguished high contrast states of cyan, red and dark. The reversible switch between any two states can be achieved with acid/base or mechanical force/chemical vapor.