具有强烈红移至近红外区消光谱的超小中空金银纳米壳。
Ultrasmall hollow gold-silver nanoshells with extinctions strongly red-shifted to the near-infrared.
机构信息
Department of Chemistry, University of Houston, 4800 Calhoun Road, Houston, Texas 77204-5003, United States.
出版信息
ACS Appl Mater Interfaces. 2011 Sep;3(9):3616-24. doi: 10.1021/am2008322. Epub 2011 Aug 17.
Hollow gold-silver nanoshells having systematically varying sizes between 40 and 100 nm were prepared. These particles consist of a hollow spherical silver shell surrounded by a thin gold layer. By varying the volume of the gold stock solution added to suspensions of small silver-core templates, we tailored the hollow gold-silver nanoshells to possess strong tunable optical extinctions that range from the visible to the near-IR spectral regions, with extinctions routinely centered at ∼950 nm. The size and morphology of these core/shell nanoparticles were characterized by dynamic light scattering (DLS), field emission scanning electron microscopy (FE-SEM), and transmission electron microscopy (TEM). Separately, X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS) were used for measuring their elemental composition; UV-vis spectroscopy was used to evaluate their optical properties. Given their relatively small size compared to other nanoparticles that absorb strongly at near IR wavelengths, these easy-to-synthesize particles should find use in applications that require ultrasmall nanoparticles with extinctions comfortably beyond visible wavelengths (e.g., medicinal therapies, diagnostic imaging, nanofluidics, and display technologies).
我们制备了尺寸在 40 至 100nm 之间呈系统变化的中空金-银纳米壳。这些颗粒由一个中空的球形银壳组成,壳外包裹着一层很薄的金层。通过改变加入到小银核模板悬浮液中的金储备溶液的体积,我们可以将中空金-银纳米壳调谐为具有强可调谐光消光特性,消光范围从可见光谱到近红外光谱区域,其消光通常集中在约 950nm。这些核/壳纳米粒子的尺寸和形态通过动态光散射(DLS)、场发射扫描电子显微镜(FE-SEM)和透射电子显微镜(TEM)进行了表征。此外,X 射线衍射(XRD)、能谱(EDS)和X 射线光电子能谱(XPS)用于测量它们的元素组成;紫外可见光谱用于评估它们的光学性质。与其他在近红外波长强烈吸收的纳米粒子相比,这些易于合成的粒子由于其尺寸相对较小,因此应该在需要具有超出可见光波长的消光的超小纳米粒子的应用中得到应用(例如,医疗治疗、诊断成像、纳流控和显示技术)。