Shi Tengda, Liang Pei, Zhang Xiubing, Zhang De, Shu Haibo, Huang Jie, Yu Zhi, Xu YongQuan
College of Optical and Electronic Technology, China Jiliang University, 310018 Hangzhou, China.
College of Optical and Electronic Technology, China Jiliang University, 310018 Hangzhou, China.
Spectrochim Acta A Mol Biomol Spectrosc. 2020 Nov 5;241:118611. doi: 10.1016/j.saa.2020.118611. Epub 2020 Jun 18.
An ex situ method was used to synthesize noble metals and metal oxide composite materials, due to the selective adsorption properties of metal oxides, the adsorption of different probe molecules by this composite structure had been studied. In the ex situ approach, we use (3-aminopropyl) diethoxy methylsilane (ATES) as a coupling agent which is easy for noble metal nanoparticles deposited on metallic oxide nanomaterials. The Raman scattering (SERS) substrate of 1D MoO nanowires (MoO-NWs) @Ag nanoparticles (Ag-NPs) hybrid surface had been fabricated. Several parameters are presented in the following which influences the morphology of self-assembly and SERS activity: (i) coupling agent of ATES, (ii) ATES content (iii) Ag-NPs content. The finite difference time domain (FDTD) method is to explain the enhancement mechanism distribution of the hybrid substrate. Different probe molecules (R6G, Methylene Blue, Crystal Violet, and 4-ATP) have been adsorbed for SERS tests. Improved principle component analysis (PCA) is adopted to obtain the minimum detection limit of probe molecules. Through the DFT calculation, different absorption strengths between the target molecules and the MoO(010) surface have been illustrated, which is also the main reason for the selective enhancement effect of MoO@Ag hybrid nanostructures. This paper might propose a method to prepare such enhancement substrate based on the selective absorption properties of oxide semiconductors.
采用非原位方法合成了贵金属与金属氧化物复合材料，基于金属氧化物的选择性吸附特性，研究了该复合结构对不同探针分子的吸附情况。在非原位方法中，我们使用（3-氨丙基）二乙氧基甲基硅烷（ATES）作为偶联剂，便于将贵金属纳米颗粒沉积在金属氧化物纳米材料上。制备了一维MoO纳米线（MoO-NWs）@Ag纳米颗粒（Ag-NPs）混合表面的拉曼散射（SERS）基底。以下给出了几个影响自组装形态和SERS活性的参数：（i）ATES偶联剂，（ii）ATES含量，（iii）Ag-NPs含量。采用时域有限差分（FDTD）方法解释混合基底的增强机制分布。吸附了不同的探针分子（罗丹明6G、亚甲基蓝、结晶紫和4-氨基硫酚）用于SERS测试。采用改进的主成分分析（PCA）来获得探针分子的最低检测限。通过密度泛函理论（DFT）计算，阐明了目标分子与MoO(010)表面之间不同的吸附强度，这也是MoO@Ag混合纳米结构选择性增强效应的主要原因。本文可能基于氧化物半导体的选择性吸附特性提出了一种制备此类增强基底的方法。
