Synthesis and photophysics of organic molecules with solvent-dependent dual fluorescent emission

• Main Authors: Zhi-Sheng Zhang, 張智勝
• Other Authors: Jinn-Hsuan Ho
• Format: Others
• Language: zh-TW
• Published: 2019
• Online Access: http://ndltd.ncl.edu.tw/handle/99jb7j

碩士 === 國立臺灣科技大學 === 化學工程系 === 107 === Based on the previous study we found that 9,10-di(2-thienyl)anthracene (2TA2T) and 9,10-di(2,2’-bithiophen-5-yl)anthracene (TTATT) have show the phenomenon of solvent-dependent dual fluorescent emission. 2TA2T shows a single fluorescent emission of 447 nm in dichloromethane, but a dual fluorescent emission of 439 and 563 nm in cyclohexane which makes the sample white-light emitting appearance. TTATT shows a single fluorescent emission of 494 nm in dichloromethane, but a dual fluorescent emission of 480 and 738 nm in cyclohexane whose wavelengths are partly located in the near-infrared region. We want to figure out that the reason make the phenomenon, we first synthesized a series compounds with anthracene as core. In the UV／PL measurement found that the compounds with 2TA2T as core all showed the dual emission phenomenon. Cosequently, we change the excitation wavelength to measure the fluorescence spectrum. And the result showed there is not quantum dot effect exist. Additionally, we also do the excitation spectrum measuremen, we used the wavelength with first emission peak and second emission peak. The result prove that both the emission are the same resource. Besides, we used different ration of dichloromethane and cycohexane as test solution. We found as the ratio of cyclohexane rise as the emission intensity rise. Therefore it exclude the reason of molecular stacking. Finally, we think the compounds with 2TA2T as core structure conform excimer in cyclohexane and make the dual emission phenomenon.