论文部分内容阅读
利用高温溶剂热法合成NaYF_4∶Yb~(3+),Ho~(3+)上转换纳米粒子(UCNPs),并利用反相微乳液法在纳米颗粒上包覆一层SiO_2,形成NaYF_4∶Yb~(3+),Ho~(3+)@SiO_2核壳结构(UCNPs@SiO_2)。通过XRD、TEM、傅里叶转换红外光谱及荧光光谱对所合成的材料进行表征。结果表明,UCNPs晶相为纯六方相,粒径约45nm,SiO_2成功包覆在UCNPs上,壳层厚约15nm;在980nm近红外光激发下发射542nm绿光。UCNPs@SiO_2上转换发光材料在生物成像中有潜在的应用。
NaYF 4: Yb 3+ and Ho 3+ were synthesized by high temperature solvothermal method. The nanoparticles were coated with SiO_2 by reverse microemulsion to form NaYF_4: Yb ~ (3 +), Ho ~ (3 +) @ SiO_2 core-shell structure (UCNPs @ SiO_2). The synthesized materials were characterized by XRD, TEM, Fourier transform infrared spectroscopy and fluorescence spectroscopy. The results show that the crystal phase of UCNPs is a pure hexagonal phase with a particle size of about 45 nm. SiO 2 is successfully coated on the UCNPs with a shell thickness of about 15 nm. A green light of 542 nm is emitted under 980 nm near-infrared excitation. UCNPs @ SiO_2 upconversion luminescent materials have potential applications in bioimaging.