DC Field | Value | Language |
---|---|---|
dc.contributor.advisor | Jeon, Duk Young | - |
dc.contributor.advisor | 전덕영 | - |
dc.contributor.author | Kim, E Su | - |
dc.contributor.author | 김이수 | - |
dc.date.accessioned | 2017-03-29T02:35:44Z | - |
dc.date.available | 2017-03-29T02:35:44Z | - |
dc.date.issued | 2014 | - |
dc.identifier.uri | http://library.kaist.ac.kr/search/detail/view.do?bibCtrlNo=657454&flag=dissertation | en_US |
dc.identifier.uri | http://hdl.handle.net/10203/221599 | - |
dc.description | 학위논문(석사) - 한국과학기술원 : 신소재공학과, 2014.2 ,[vii, 82 p. :] | - |
dc.description.abstract | NIR-emitting $CuInS_2/ZnS$ QDs were synthesized by off-stoichiometry effect, and the tuned emission wavelength is 850nm which is proper to deep tissue imaging. Due to the cation-exchange phenomena, however, the emission wavelength of synthesized CIS core was blue-shifted after ZnS shell coating. In order to inhibit this blue-shift of photoluminescence, controlling the synthesis temperature during ZnS shell coating was required, and the selected synthesis temperature were $180^\circ C$, $210^\circ C$, $230^\circ C$ and $250^\circ C$. Temperature effect on CIS/ZnS QDs could be related to substitutional diffusion mechanism expressed by Fick’s law. The least blue-shifted emission wavelength was 810nm and degree of blue-shift is about 40nm. Also, not only blue-shift but also the different evolution of PL peak components was observed as ZnS coated on the surface of CIS core. These PL peak components were related to defect-level emission of CIS/ZnS QDs, and could be confirmed by low-temp PL and proposed defect diagram of Cu-rich CIS. Four PL peak components were contained and the change of longer energy peaks could be related to cation-exchange. The degree of passivation by ZnS shell for different synthesis temperatures, results in QY (26-38%). To confirm the possibility of applying CIS/ZnS QDs to bio-imaging, the experiment for exchange hydrophobic QDs to hydrophilic QDs was progressed using HSA/PEG encapsulation method. The 6-armend PEG-NHS was used as an amphiphilic ligand, and the fluorescent intensity was decreased to 57% of initial QDs after fabrication of QD-HSA/PEG nanocapsule and the size of nanocapsule was 140 $\pm$ 21.6nm which measured by SEM and TEM. According to these results, this synthesized NIR-emitting CIS.ZnS QDs using inhibiting cation-exchange, are suitable for bio-application, especially in vivo-imaging. | - |
dc.language | eng | - |
dc.publisher | 한국과학기술원 | - |
dc.subject | CIS/ZnS QDs | - |
dc.subject | cation exchange | - |
dc.subject | temperature effect | - |
dc.subject | NIR emitting | - |
dc.subject | PEG nanocapsule | - |
dc.subject | CIS/ZnS 양자점 | - |
dc.subject | 양이온 치환 | - |
dc.subject | 온도 조절 | - |
dc.subject | 근적외선 발광 | - |
dc.subject | PEG 나노캡슐 | - |
dc.title | Synthesis of efficient near-Infrared-emitting $CuInS_2/ZnS$ quantum dots by inhibiting cation-exchange for bio application | - |
dc.title.alternative | 양이온 치환 억제를 통한 바이오 이미징용 근적외선 발광 고효율 $CuInS_2/ZnS$ 양자점의 합성 | - |
dc.type | Thesis(Master) | - |
dc.identifier.CNRN | 325007 | - |
dc.description.department | 한국과학기술원 :신소재공학과, | - |
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