Institut de Recherche Interdisciplinaire, CNRS USR 3078, Université Lille 1, Parc de la Haute Borne, 50 avenue de Halley, 59658 Villeneuve d'Ascq, France.
ACS Appl Mater Interfaces. 2013 Aug 14;5(15):7042-9. doi: 10.1021/am401313x. Epub 2013 Jul 24.
A new family of luminescent and stable silicon-based nanoparticles (NPs), silica cross-linked pluronic F127 (PF127) micelles loaded with decyl capped silicon nanoparticles (decyl-SiNPs), were synthesized in aqueous media. The decyl-SiNPs were prepared by first liberating hydride terminated SiNPs (H-SiNPs) from a porous silicon matrix followed by their functionalization via hydrosilylation with 1-decene under photochemical activation. The silicon-based NPs exhibit bright photoluminescence (PL) with a quantum yield of ∼3.8% and peaking at ∼2.0 eV, which lies within the transmission window that is useful for biological imaging. They display a hydrodynamic size of ∼25 nm with exterior polyethylene oxide (PEO) blocks stretching out in aqueous media. Chloroform was found to quench the excitation at energy above 4.9 eV by shielding the incident light or relaxing the charge carriers, which highlights that caution against solvent interference should be taken when performing the studies on PL origin and luminescence efficiency of SiNPs. For PF127, the blocks of hydrophilic PEO participate in the PL quenching, while poly(propylene oxide) (PPO) does not. The colloidal solution displays excellent PL stability against salt (NaCl) and temperature but is susceptible to basic solution at pH above 9.
一种新型发光且稳定的硅基纳米粒子（NPs）家族，即交联的聚醚 F127（PF127）胶束负载癸基封端硅纳米粒子（decyl-SiNPs），在水介质中被合成。decyl-SiNPs 是通过首先从多孔硅基质中释放出氢化硅纳米粒子（H-SiNPs），然后通过在光化学激活下与 1-癸烯的硅氢化反应对其进行功能化来制备的。这些硅基 NPs 具有明亮的光致发光（PL），量子产率约为 3.8%，峰值约为 2.0 eV，这处于对生物成像有用的传输窗口内。它们在水介质中显示出约 25nm 的水动力学尺寸，外部的聚乙烯氧化物（PEO）块伸展出来。发现氯仿通过屏蔽入射光或松弛电荷载流子来猝灭能量高于 4.9eV 的激发，这突出表明在研究 SiNPs 的 PL 起源和发光效率时应注意避免溶剂干扰。对于 PF127，亲水性 PEO 块参与 PL 猝灭，而聚（氧化丙烯）（PPO）则不参与。胶体溶液对盐（NaCl）和温度表现出优异的 PL 稳定性，但对 pH 值高于 9 的碱性溶液敏感。
