基于Au、Ag纳米材料的表面增强拉曼散射(SERS)光谱能够获得单分子的结构演化与功能转化等丰富的动态信息，在物理/材料/生命/医学等领域备受关注。有效调控制备出具有优异SERS特性的复合纳米构型是目前的关键问题。本申请项目选取六方氮化硼(h-BN)二维材料，利用激光液相辐照技术在Au、Ag离子溶液中可控合成h-BN/Au@Ag纳米复合材料。改变辐照参数和金属离子浓度有效控制Au、Ag负载生长，进而调控Au/Ag相对含量。利用h-BN的比表面积大、双金属的协同效应等特点，通过Au/Ag组份调控，研究SERS光谱的演化规律，探索能够显著提高SERS性能的最佳h-BN/Au@Ag复合构型；结合光激发的理论分析，探索优异SERS性能与纳米构型之间的隐含关联及其产生的内在物理机制。预期成果为后续促进SERS应用研究奠定基础，而且为调控制备其他二维/金属复合材料提供依据，进而扩展众多领域的交叉研究。

Based on the irradiation of Au, Ag nanomaterials, the surface-enhanced Raman scattering (SERS) spectroscopy can provide ultrasensitive dynamic information of single molecule, which has received increasing attention in the physics/materials/biology/medical sciences. So, the development of new methods for conveniently synthesizing SERS-active nanocomposites is very important. In this project, the novel nanocomposites based on overgrowth of bimetallic Au@Ag nanoparticles on hexagonal boron nitride (h-BN) surfaces will be synthesized by laser irradiation-induced photochemical approach. The moderate overgrowth process allows one to control the Au@Ag nanostructures and manipulate the corresponding composition. Superior to traditional approaches, the Au@Ag nanoparticles with controllable compositions can be adjusted by simply changing the laser parameters and metallic ions contents. Then, based on the as-prepared h-BN/Au@Ag nanocomposites with controllable metallic compositions, the excellent SERS performances will be illustrated in this project. It is our intension to optimize the bimetallic Au@Ag structures that can provide maximized SERS activity. The simulated near-field electromagnetic field distribution of the h-BN/Au@Ag nanocomposties and the pronounced inter-metallic synergies can predict the theoretical hotspots for amplifying SERS signals. The expected results in this project have significant implications for ultrasensitive biological and biomedical SERS analyses, which will also stimulate the further investigation for sculpting other novel 2D/metallic nanocomposites in various applications.