通过化学浴沉积的方法制备了一种高SERS活性和重复性的银薄膜衬底。分别采用扫描电子显微镜和拉曼光谱研究了沉积时间对银薄膜微观形貌和SERS活性的影响, 优化的沉积时间为120分钟。利用优化的银薄膜衬底, 可以检测到10-9 M 的罗丹明分子的SERS谱图, 表明该银薄膜衬底具有很高的SERS活性。相同实验条件下, 在一片银薄膜衬底上任意选择16个点测试R6G的SERS谱图。分别计算了R6G的8个特征峰16次检测的相对标准偏差, 最大相对标准偏差小于13% 。实验结果表明, 该衬底具有很好的重复性, 可应用于SERS 的定量分析。采用优化的银薄膜衬底检测了不同浓度的芥子气及其水解产物硫二甘醇。分别结合芥子气和硫二甘醇的常规拉曼光谱和文献报道, 对它们的SERS谱图进行了指认和归属。20分钟内, 对芥子气和硫二甘醇的检测限可分别达到320 ppm和1 ppm (g/g)。

In this study, a silver film substrate with highly reproducibility and SERS activity was fabricated based on a chemical-bath-deposition method. The effects of deposition time of silver films on morphology and SERS activity were investigated by FE-SEM and Raman spectroscopy, respectively. The optimized deposition time was 120 min. R6G molecule of 10-9 M could be detected by SERS using the optimized silver film. We collected SERS spectra of R6G molecules from 16 randomly selected positions on the optimized silver film substrate under the same experimental conditions. The maximum relative deviation values of signal intensities of major SERS peaks of R6G were below 0.13, revealing a good reproducibility across the entire area of the substrate. Then, the optimized silver films were used for detecting trace mustard (HD) and its hydrolysis product thiodiglycol (TDG). SERS spectra of HD and TDG were assigned according to their normal Raman spectra. The limit of detection for HD and TDG were 320 ppm and 1 ppm within 20 minutes, respectively.