过渡金属化合物纳米材料表面增强拉曼光谱的实验和理论研究

Typical transition metal (Cu, Zn, Ni, Sn, Pb, etc) compounds and their composite nano system with noble metal are to be studied experimentally and theoretically. The morphology and structure of well synthesized nano material is characterized by SEM, TEM and UV-vis spectroscopy, while their optical and surface enhanced properties are investigated via surface-enhanced Raman spectroscopy(SERS). Further quantum calculations and electromagnetic simulations are introduced on the basis of three-dimensional Finite Difference Time Domain (3D-FDTD) and Density Functional Theory (DFT) to better understand the physical and chemical enhancement mechanisms of transition metal compounds nano material. The influence factors such as material, size, shape, and environment will be discussed as well to reveal the inherent mechanisms for Raman enhancement. The integrated investigation is expected to improve the surface enhancement properties of transition metal compound nano material and to promote practical explorations on their extensive application such as near-field coupling enhancement, LSPR sensor, surface catalysis and even elements in optical nanocircuits.

本研究以典型的过渡金属（铜、锌、镍、锡、钯等）化合物纳米材料,以及贵金属-过渡金属化合物纳米材料复合体系为主要研究对象，运用SEM、TEM、紫外可见光谱等多种技术进行形貌结构表征，并通过表面增强拉曼光谱考察过渡金属纳米材料的光学性质及表面增强特性。在此基础上我们利用密度泛函理论和三维有限时域差分对过度金属纳米材料的增强性质进行量化理论模拟和电磁模拟，分析过渡金属化合物纳米材料表面增强拉曼信号的化学和物理机制，并探讨不同材料、尺寸、形貌、环境等因素对表面增强过程的影响，揭示过渡金属纳米材料的表面增强的内在机制。选择表面增强性能优异的过渡金属化合物纳米材料，发展过渡金属化合物纳米材料在近场耦合增强、LSPR传感、表面催化、纳米光学元件等领域的应用。

课题以典型的过渡金属（铜、钛、钼等）化合物纳米材料，以及过渡金属化合物/金钠米颗粒和石墨稀/金钠米颗粒复合体系为主要研究对象，运用扫描电镜、透射电镜、紫外可见光谱和表面增强拉曼光谱（SERS）等技术对制备得到的氧化亚铜, 二氧化钛/金纳米颗粒, 三氧化钼/金纳米颗粒, 二硫化钼/金纳米颗粒和石墨稀/金纳米颗粒等SERS基底材料进行形貌结构和性质表征。为了考察材料在SERS过程中的光学性质及表面增强特性，我们引入密度泛函理论（DFT）量化模拟和三维有限时域差分方法（3D-FDTD）电磁模拟对相关的化学和物理机理进行系统性的讨论，分析材料、尺寸、形貌、环境等因素对表面增强过程的影响，揭示宏观性质与微观结构的内在联系，发现并优化具有优异表面增强性能的化合物和化合物/贵金属复合纳米结构，发展新型纳米材料在表面增强技术、LSPR传感、表面催化、纳米光学元件等领域的应用。