Bartosewicz Bartosz, Michalska-Domańska Marta, Liszewska Malwina, Zasada Dariusz, Jankiewicz Bartłomiej J
Institute of Optoelectronics, Military University of Technology, Kaliskiego 2 Str. 00-908 Warsaw, Poland.
Faculty of Advanced Technologies and Chemistry, Military University of Technology, Kaliskiego 2 Str. 00-908 Warsaw, Poland.
Beilstein J Nanotechnol. 2017 Oct 5;8:2083-2093. doi: 10.3762/bjnano.8.208. eCollection 2017.
Core-shell nanostructures have found applications in many fields, including surface enhanced spectroscopy, catalysis and solar cells. Titania-coated noble metal nanoparticles, which combine the surface plasmon resonance properties of the core and the photoactivity of the shell, have great potential for these applications. However, the controllable synthesis of such nanostructures remains a challenge due to the high reactivity of titania precursors. Hence, a simple titania coating method that would allow better control over the shell formation is desired. A sol-gel based titania coating method, which allows control over the shell thickness, was developed and applied to the synthesis of Ag@TiO and Au@TiO with various shell thicknesses. The morphology of the synthesized structures was investigated using scanning electron microscopy (SEM). Their sizes and shell thicknesses were determined using tunable resistive pulse sensing (TRPS) technique. The optical properties of the synthesized structures were characterized using UV-vis spectroscopy. Ag@TiO and Au@TiO structures with shell thickness in the range of ≈40-70 nm and 90 nm, for the Ag and Au nanostructures respectively, were prepared using a method we developed and adapted, consisting of a change in the titania precursor concentration. The synthesized nanostructures exhibited significant absorption in the UV-vis range. The TRPS technique was shown to be a very useful tool for the characterization of metal-metal oxide core-shell nanostructures.
核壳纳米结构已在许多领域得到应用，包括表面增强光谱学、催化和太阳能电池。包覆二氧化钛的贵金属纳米颗粒结合了核的表面等离子体共振特性和壳的光活性，在这些应用中具有巨大潜力。然而，由于二氧化钛前驱体的高反应活性，此类纳米结构的可控合成仍然是一个挑战。因此，需要一种能更好控制壳层形成的简单二氧化钛包覆方法。开发了一种基于溶胶-凝胶的二氧化钛包覆方法，该方法可控制壳层厚度，并将其应用于合成具有不同壳层厚度的Ag@TiO和Au@TiO。使用扫描电子显微镜（SEM）研究了合成结构的形态。使用可调电阻脉冲传感（TRPS）技术确定了它们的尺寸和壳层厚度。使用紫外-可见光谱对合成结构的光学性质进行了表征。采用我们开发并改进的方法，通过改变二氧化钛前驱体浓度，制备了壳层厚度分别约为40-70nm（针对Ag纳米结构）和90nm（针对Au纳米结构）的Ag@TiO和Au@TiO结构。合成的纳米结构在紫外-可见范围内表现出显著吸收。TRPS技术被证明是表征金属-金属氧化物核壳纳米结构的非常有用的工具。
