K2MF6:Mn4+(Si, Ti, Eu, Y) 형광체 발광특성 및 다중껍질 InP/ZnS 양자점의 자외선 열화특성 연구: Photoluminescent property of K2MF6:Mn4+(Si, Ti, Eu, Y) phosphors and a comparative study of multiple-shell InP/ZnS quantum dots on the photo-degradation of UV radiation

by Doyoung Jeong (MS Candidate)

Friday May 22, 2015, 5:10 PM → 5:40 PM Asia/Seoul

206호 (제1과학관)

K2SiF6:Mn4+ phosphor, K2MF6:Mn4+(M=Ti, Eu, Y) phosphor using the cation exchange method and InP/ZnS(Core/Shell) quantum dot were successfully synthesized. And the photoluminescence properties were compared, the UV degradation property of InP/ZnS quantum dot was researched. The photoluminescence (PL) spectrum of as-synthesized K2SiF6:Mn4+ phosphors showed a narrow emission band with 5 peaks in wavelength raging from 610 to 650 nm. The main peak at 630 nm had a narrow full width at half- maximum (FWHM) (<10 nm). The luminescent intensity of K2SiF6:Mn4+ phosphor was about 1.5 times higher than that of the K2TiF6:Mn4+ phosphors. Non-Cd InP/ZnS quantum dots were synthesized, which used tris(dimethylamino)phosphine(P(N(CH3)2)) as a phosphorus precursor. InP/ZnS quantum dots had sole emission peak with a full width at half-maximum (FWHM) (50 nm). The luminescent intensity was dependant on the synthesis time of ZnS shell. The QD samples (InP/ZnS, InP/ZnS/ZnSe, InP/ZnS/SiO2) were synthesized in order to compare the UV stability. The luminescent intensity of multiple- shell QDs was lower than that of InP/ZnS sample. On the UV lamp, InP/ZnS/ZnSe, InP/ZnS samples was extinct in 15 hours, but InP/ZnS/SiO2 sample steadily emitted on the UV source.

Thesis Advisor: Prof. Dohyung Kim