Triphenylamine(TPA) 작용기를 도입한 DPP 염료의 Charge Transfer로 인한 형광소광과 극성 조건에 따른 고체형광 구현에 관한 연구

Aggregation Induced Emission Enhancement;Charge Transfer;Diketopyrrolopyrrole;620.1

공과대학 재료공학부 ;

University:서울대학교 대학원

关键词: Aggregation Induced Emission Enhancement;    Charge Transfer;    Diketopyrrolopyrrole;    620.1;   

Others  :  http://s-space.snu.ac.kr/bitstream/10371/161046/1/000000158427.pdf

美国|英语

来源: Seoul National University Open Repository

【 摘 要 】

Organic dyes have excellent fluorescence properties, but they have limitations in applications due to fluorescence quenching of H-aggregation when aggregation occurs. However, by introducing TPA functional group and using Aggregation Induced Emission Enhancement (AIEE) phenomenon, it is possible to prevent the loss of energy in the aggregated state and induce J-aggregation, thereby increasing the fluorescence efficiency in the solid state. In this study, three new dyes, induced TPA functional groups, were synthesized based on Diketopyrrolopyrrole(DPP), which is being studied for application to various fields due to its high fluorescence properties and low toxicity. The comparison with the dye without TPA was proceeded and it was confirmed whether it showed a tendency in fluorescence properties.The fluorescence quantum yield (QY) was measured at two different conditions to confirm that the AIEE phenomenon due to introduction of the TPA functional group is normally activated. As a result of measurement, AIEE was not activated in experiment, formed aggregation by mixed solvent, and AIEE was activated in experiment, formed aggregation in frozen solvent by liquid nitrogenAs a result of comparing the conditions of the two experiments, it was judged that the absence of the AIEE phenomenon in the mixed solvent experiment was probably due to the polarity of the solvent, and it was thought that this was the Charge Transfer (CT) phenomenon due to the Donor-Acceptor. So the experiment to confirm was carried out. Experimental results showed that the CT effect occurred in the TPA1, TPA2, ETPA dyes. It was confirmed that the fluorescence quenching phenomenon was caused by CT and that this phenomenon occurs well in high polarity environment.Therefore, it was concluded that low polarity conditions should be applied to achieve high solid fluorescence. To confirm this, we fabricated films with low polarity and high polymer and measure QY of films. And then comparing QY of films with QY of solvent state. As a result of the measurement, it was confirmed that HT, which is a control group, exhibited a low QY value due to aggregation regardless of the polarity in the film state as compared with the solvent phase. In the case of TPA1, TPA2, ETPA fluorescence quenching due to aggregation occurred in the high polarity film, and higher or similar level of fluorescence was observed in the low polarity film than in the solvent phase.In this study, we have observed the AIEE of DPP-based dyes and confirmed that when TPA functional group is introduced into DPP, the effect of AIEE may be reduced due to CT.Therefore, when the TPA functional group is introduced to improve the solid fluorescent emission, the CT, due to the D-A structure may occur in high polarity environment and fluorescence quenching also do. If the low polarity environment is established at this time, the high solid fluorescence property will be obtained.