摘要：表面增强拉曼散射(SERS)是一种可以实现超低浓度，甚至是单分子检测的新兴检测手段。目的是要通过增强待测物质的拉曼信号来提高其检测的灵敏度，从而快速地检测出常规条件下无法检测的物质。

本文采用液相法制备银-碳复合材料，将制备的材料作为SERS基底，来检测探针分子罗丹明6G（R6G）的拉曼散射信号。首先，结合液相法与模板法，以葡萄糖和硝酸银为原料、三辛胺（TOA）为软模板，制备了Ag/C中空纳米复合微球。通过EDS、FT-IR、Raman等手段表征了样品的化学成分、官能团和石墨化程度，利用SEM表征产物的形貌特征。其次，采用液相法，以葡萄糖和硝酸银为原料，制备了Ag@C核壳纳米复合材料。通过EDS、XRD、TEM等手段，对产物的化学成分及形貌进行表征。探索不同碳/银比、反应时间及加入的TOA量等条件下合成产物的性能差异。以不同条件下制备的Ag/C中空纳米复合微球和Ag@C核壳纳米复合材料为SERS基底，测试对R6G的拉曼增强效果，得到制备SERS基底的最佳反应条件。

关键词  液相法  Ag/C中空复合微球  Ag@C核壳纳米复合材料  表面增强拉曼散射

毕业设计说明书外文摘要

Title  The synthesis of Ag-C nanocomposites through liquid phase method and the exploration of its properties

Abstract:Surface-enhanced Raman scattering (SERS) is a new detecting method which can detect samples with ultra-low concentration or even single molecule. The principle of the method is to increase the sensitivity of the detection by increasing the Raman signal of the substance which is tested. Through this way, substance could be detected rapidly, which could not realize under common conditions.

Silver-carbon composites were prepared by liquid-phase method, which were used as SERS substrates to detect the Raman scattering signal of rhodamine 6G (R6G). First, Ag/C hollow nanocomposite microspheres were prepared via liquid phase method along with template method, with glucose and silver nitrate as raw materials and trioctylamine (TOA) as template. The chemical compositions, functional groups and graphitization degree of the samples were characterized by EDS, FT-IR and Raman. The morphological characteristics of the products were characterized by SEM. Second, Ag@C core-shell nanocomposites were prepared through liquid phase method with glucose and silver nitrate as raw materials. The chemical compositions and morphologies of the products were characterized by EDS, XRD and TEM. Different performances of samples, which were synthesized under different carbon/silver ratio, reaction time and the amount of TOA, were thoroughly explored. Ag/C hollow nanocomposite microspheres and Ag@C core-shell nanocomposites, which were prepared under different conditions, were used as SERS substrates, to explore the efficiency of Raman single enhancement of R6G. Optimum reaction conditions of SERS substrates were obtained.

Keywords  Hydrothermal method  Ag/C hollow nanocomposites  Ag@C core-shell structure  SERS

目   次

1  绪论 1

1.1  贵金属纳米材料简介 1

1.2  核壳型贵金属纳米复合材料 2

1.3  表面增强拉曼散射 3

1.4  本课题的研究意义 5

1.5  本课题的研究内容 5

2  Ag/C中空复合微球的制备及其SERS效应研究 6

2.1  实验仪器及药品 6

2.2  实验过程 6

2.3  产物表征 7

2.4  本章小结 11

3  Ag@C核壳纳米复合材料的制备及其SERS效应研究 12

3.1  实验过程 12

3.2  实验试剂及实验仪器 12

3.3  不同体积TOA制备的Ag@C核壳复合纳米材料 12

3.4  不同碳/银比制备的Ag@C核壳复合纳米材料 14

3.5  不同反应时间制备的Ag@C核壳复合纳米材料 17

3.6  本章小结 19