为了研究ZnO/Au复合薄膜中不同浓度的金纳米颗粒对表面增强拉曼光谱(SERS)的影响, 通过光还原反应将Au纳米颗粒沉积在ZnO薄膜上作为活性基底形成ZnO/Au 复合薄膜, 实现SERS基底的制备。通过X射线衍射(XRD)、扫描电子显微镜(SEM)和EDS元素分析对样品进行性质表征, 发现制备的ZnO薄膜均匀密布于玻璃衬底上, 且金纳米颗粒成功地沉积在ZnO表面。利用探针式台阶仪测得ZnO薄膜的厚度为50 nm。以低浓度罗丹明B(10-9 M)作为探针分子, 改变Au纳米颗粒的浓度, 进行SERS测试。结果表明, ZnO/Au复合薄膜具有良好的拉曼增强效应, 在620 cm-1, 1355 cm-1, 1502 cm-1, 1646 cm-1等位置出现了罗丹明B的明显特征峰。对比ZnO/Au复合薄膜中不同浓度的金纳米颗粒对检测罗丹明B的SERS增强效果, 发现3 g·L-1浓度下拉曼活性增强效果最佳。

In order to study the influence of gold nanoparticles with different concentrations in ZnO/Au composite film on Surface-Enhanced Raman Scattering (SERS), Au nanoparticles were deposited on ZnO film as an active substrate to form ZnO/Au composite film by photoreduction reaction, so on to realize the fabrication of SERS substrate. The properties of the samples were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM) and EDS elemental analysis, we find that the prepared ZnO films are uniformly densely coated on the glass substrates and the gold nanoparticles are successfully deposited on the ZnO surface. The thickness of the ZnO film was measured by a Step Profiler to be 50 nm. Low concentration Rhodamine B (10-9 M) is used as the probe molecule and we change the concentration of Au nanoparticles for SERS test. The results show that ZnO/Au composite film has good Raman enhancement effect, and we find that the distinct characteristic peaks of Rhodamine B are at positions 620 cm-1, 1282 cm-1, 1355 cm-1, 1502 cm-1, and 1646 cm-1. Comparing the SERS enhanced effect of gold nanoparticles with different concentrations in ZnO/Au composite film on detecting rhodamine B, it is found that the Raman activity enhancement effect is the best at the 3 g·L-1 concentration.