CAJ | 학술논문

以巯基乙酸为稳定剂制备了CdSe纳米晶,通过尺寸选择沉淀得到2nm到3nm之间不同尺寸的纳米晶,利用室温光吸收,光致发光(PL)和光致发光激发(PLE)谱来研究了CdSe纳米团簇的光学性质.紫外-可见吸收谱给出了具有清晰激光特征的尖锐吸收边,这表明样品的尺寸分布很窄.光致发光研究表明,样品有两个发射带,一个具有较高能量位于吸收边,来自电子-空穴对从最低激发态能级弛豫后的辐射复合,另一个低能发射带归属于基质与纳米晶界面存在的俘获中心.PLE谱中有2个吸收带,分别是S-S和P-P跃迁.最后还给出了不同激发能量下的发光特性.
이구기을산위은정제제비료CdSe납미정,통과척촌선택침정득도2nm도3nm지간불동척촌적납미정,이용실온광흡수,광치발광(PL)화광치발광격발(PLE)보래연구료CdSe납미단족적광학성질.자외-가견흡수보급출료구유청석격광특정적첨예흡수변,저표명양품적척촌분포흔착.광치발광연구표명,양품유량개발사대,일개구유교고능량위우흡수변,래자전자-공혈대종최저격발태능급이예후적복사복합,령일개저능발사대귀속우기질여납미정계면존재적부획중심.PLE보중유2개흡수대,분별시S-S화P-P약천.최후환급출료불동격발능량하적발광특성.
Cadmium selenide nanocrystals were synthesized with mercaptoacteic acid as stabilizer and different size of nanocrystals from 2nm to 3nm were obtained by size selective precipitation.The optical properties of CdSe nanoclusters were studied by optical absorption, photoluminescence (PL) and photoluminescence excitation(PLE) spectroscopies at room temperature. The UV-vis absorption spectroscopy shows sharp absorption spectra with clear excitonic features which indicating a narrow size distribution for our samples. Photoluminescence investigation shows that our samples have two luminescence bands, a sharp high energy hand with high intensity near the absorption edge attributed to radiative recombination of electron hole pairs after relaxation to lowest quantum dot level, and the other lower energy broad band is attributed to the trapping center at the matrix interface region. More than one band appeared in the photoluminescence excitation (PLE) spectra, assigned to S-S and P-P transition. The luminescence properties obtained for different excitation are also presented.