摘要表面增强拉曼散射(Surface enhanced Raman scattering，SERS)一般可以被认为是 拉曼散射体因为在币金属（金、银、铜）、碱金属、过渡金属上的吸附而导致拉曼 信号增强的现象。分子所吸附衬底的表面形态对于 SERS 技术有着很大影响，因此 人们一直致力于研究出高性能的 SERS 衬底以获得 SERS 增强信号。本文论述了在 富集的二氧化硅表面通过化学方法生长一层聚多巴胺薄膜，再以聚多巴胺为固体还 原剂，并在其表面生长纳米银粒子从而构造出 SERS 衬底所必须的粗糙贵重金属表 面。在此基础上采用不同粒径的二氧化硅来制备衬底进行比较，同时对球的富集和 纳米银离子生长的顺序进行了对比。另外通过偏光显微镜、SEM、XRD 以及拉曼 等检测方法可以对获得的衬底进行性能测试。通过进行多次实验对比和检测可以获 得表面增强拉曼散射所需的衬底。81505

通过本文论述的两个方案都可以实现制作出 SERS 衬底的目的。经过计算增强 因子可以达到 105。通过两种方案的对比可以发现方案一中在生长纳米银粒子之前 先对 SiO2@PDA 粒子进行抽滤，其增强效果要优于方案二中生长完粒子再富集的效 果。另外这两个方案制备的衬底在经历了半个月后拉曼检测时仍然有信号产生，说 明衬底的保存时间较长。这样多巴胺作为二次反应平台，同时又作为还原剂在进行 SERS 衬底制作过程中实现了过程简单、周期短以及性能在较长时间里可以保持在 一定的稳定水平的目的，达到了预期的效果。

毕业论文关键词：SERS；二氧化硅；多巴胺；衬底

Abstract Raman scattering adsorbing on the coin metal (Au， Ag， Cu)， alkali metals and transition metal has led to the enhancement of Raman signal。 This phenomenon is considered as Surface enhanced Raman scattering。 The surface morphology of molecules

adsorbed on the substrate has a great impact on the SERS technology， so people   have

been working on the research of SERS substrate with high performance to obtain the SERS enhanced signal。 This article discusses a way that the thin film of poly dopamine grows on the surface of the enriched silica through chemical method。 Then making poly dopamine to be a solid reductant and making nano-silver particles grow on the surface of poly dopamine at the same time。 This method can be used to construct the surface of

rough precious metal which is necessary for SERS substrate。 On this basis， the substrate

is prepared by using silica with different particle sizes for comparison， and the different sequence of enrichment of the ball with the growth of nano-silver ions is compared at the same time。 In addition，SEM，XRD，Raman and other test methods can be used to test the performance of the substrate。 The substrate required for surface enhanced Raman

scattering can be obtained by means of comparison and detection。

The two schemes discussed in this paper can achieve the purpose of making the SERS substrate。 The calculated enhancement factor can reach 105。 By comparison， the reinforcing effect of scheme one that dealing with SiO2@PDA particle by suction before the growth of silver nano particles on poly dopamine is better than scheme two that enriching particle after their growth。 The substrates prepared by the two schemes have

still  been  detected  by  Raman  spectroscopy  for  half  a  month， and  this  means  the

preservation time of the substrate is longer。 Dopamine as secondary reaction platform， while at the same time as solid reductant in SERS substrate makes process achieve a target that simple process， short cycle and performance in a long period of time can be maintained at a certain level of stability。 This has achieved the desired effect。