Synthesis and photophysical characterization of highly luminescent silica films doped with substituted 2-hydroxyphthalamide (IAM) terbium complexes
作者:Lidia Armelao、Gregorio Bottaro、Silvio Quici、Marco Cavazzini、Chiara Scalera、Gianluca Accorsi
DOI:10.1039/c1dt11131k
日期:——
Innovative Tb3+ antenna complexes employing two different substituted 2-hydroxyphthalamide ligands (HxOH-IAM and bis-HxOH-IAM) acting simultaneously as coordinating sites and light collector units have been synthesized and successively anchored in silica layers by the sol–gel technique. The complexes show remarkable photoluminescence (PL) quantum yields in methanol solution, as high as 0.30 and 0.40 for (HxOH-IAM)4⊂Tb3+ and (bis-HxOH-IAM)2⊂Tb3+, respectively. The grafting of the Tb3+ complexes in silica single layers accomplished by exploiting the terminal hydroxyl groups of the IAM chains results in highly transparent and homogeneous films displaying bright green emission and PL efficiencies of up to 0.40. The silica layers containing the (bis-HxOH-IAM)2⊂Tb3+ show remarkable photostability even under prolonged and continuous irradiation (up to 3.5 h). The nature of the IAM ligands allows the photoexcitation of the complexes at wavelengths even longer than 350 nm, which is a spectral window suitable to develop luminescent lanthanide probes dedicated to bioanalyses and bioimaging applications.
通过溶胶-凝胶技术,合成了采用两种不同取代的 2- 羟基邻苯二甲酰胺配体(HxOH-IAM 和 bis-HxOH-IAM)同时作为配位位点和集光单元的创新 Tb3+ 天线配合物,并将其先后锚定在二氧化硅层中。这些复合物在甲醇溶液中显示出显著的光致发光(PL)量子产率,(HxOH-IAM)4⊂Tb3+和(bis-HxOH-IAM)2⊂Tb3+的量子产率分别高达 0.30 和 0.40。通过利用 IAM 链的末端羟基将 Tb3+ 复合物接枝到二氧化硅单层中,可获得高度透明和均匀的薄膜,并显示出明亮的绿色发射,聚光效率高达 0.40。含有 (bis-HxOH-IAM)2⊂Tb3+ 的二氧化硅层即使在长时间连续照射(长达 3.5 小时)的情况下也能显示出显著的光稳定性。IAM 配体的性质允许复合物在波长甚至长于 350 纳米的波长上发生光激发,这是一个光谱窗口,适合开发用于生物分析和生物成像应用的发光镧系元素探针。