纳米银溶胶和微腔型光纤SERS基底的制备及其性能比较  

Preparation and Performance Comparison of Nano-Silver Sol and Micro-Cavity Fiber SERS Substrates

作　　者：付兴虎[1] 王振兴 李佳轩 马双玉 付广伟[1] 金娃 毕卫红[1] 董艳华[2] FU Xing-hu;WANG Zhen-xing;LI Jia-xuan;MA Shuang-yu;FU Guang-wei;JIN Wa;BI Wei-hong;DONG Yan-hua(School of Information Science and Engineering,the Key Laboratory for Special Fiber and Fiber Sensor of Hebei Province,Yanshan University,Qinhuangdao 066004,China;Key Laboratory of Specialty Fiber Optics and Optical Access Networks,Shanghai University,Shanghai 200444,China)

机构地区：[1]燕山大学信息科学与工程学院,河北省特种光纤与光纤传感重点实验室,河北秦皇岛066004 [2]特种光纤与光接入网省部共建重点实验室,上海大学,上海200444

出　　处：《光谱学与光谱分析》2022年第2期470-477,共8页Spectroscopy and Spectral Analysis

基　　金：国家自然科学基金项目(61675176);上海市科委重点实验室项目(SKLSFO2020-02)资助。

摘　　要：通过化学法制备了纳米银溶胶基底和微腔型光纤表面增强拉曼散射(SERS)基底,其中光纤SERS基底的微腔结构是通过氢氟酸(HF)腐蚀得到的。实验采用湿法检测,首先将纳米银溶胶基底与罗丹明6G(R6G)混合,找到增强效果最强时的裸光纤微腔结构,在此结构的基础上采用溶胶自组装法制备银纳米颗粒包覆的光纤SERS基底,通过控制自组装时间制备不同光纤SERS基底(Ag/光纤-x,其中x为自组装时间,分别为10,20,30,40,50和60 min)。以10^(-3) mol·L^(-1)的R6G为探针分子,对Ag/光纤-x基底进行初筛,得到增强效果最强的Ag/光纤-30基底。通过检测不同浓度的R6G溶液,对纳米银溶胶基底和Ag/光纤-30基底的SERS性能进行研究。实验结果表明,在相同的实验条件下,纳米银溶胶基底和Ag/光纤-30基底对R6G的检测限(LOD)分别为10^(-6)和10^(-9)mol·L^(-1);在1362 cm^(-1)拉曼位移处对两种基底的拉曼强度和浓度进行对数转换拟合,Ag/光纤-30基底的拟合优度R^(2)达0.9753,远高于纳米银溶胶基底;拉曼信号的再现性检测结果表明,两种基底在各个特征峰处的RSD值均在合理范围内,但Ag/光纤-30基底的RSD值范围更小,范围最大值仅为10.94%;两种基底的稳定性测试结果表明,纳米银溶胶基底35 d后,在1362 cm^(-1)位置处的综合拉曼强度下降了45.90%,而Ag/光纤-30基底35 d后,综合拉曼强度仅下降了17.58%,说明Ag/光纤-30基底具有长期稳定性。同时,对两种基底增强因子(REF)进行计算,对浓度为10^(-6)mol·L^(-1)的R6G溶液,纳米银溶胶基底和Ag/光纤-30基底的REF数值分别为3.49×10^(6)和2.14×10^(7),说明对于同一浓度的R6G溶液,Ag/光纤-30基底具有更强的增强效果,且比纳米银溶胶基底高出一个数量级。通过对比两种基底的SERS性能,表明Ag/光纤-30基底具有更高的灵敏度、更好的再现性以及长期稳定性。因此,基于银纳米颗粒包覆的光纤SERS基底在农残化学分析、�In this paper,nano-silver sol substrate and micro-cavity fiber surface-enhanced Raman scattering(SERS)substrate were prepared by chemical methods.The micro-cavity structure was obtained by etching with hydrofluoric acid(HF).The experiment adopts wet detection.Firstly,the nano-silver sol substrate is mixed with Rhodamine 6G(R6G)to find the bare fiber micro-cavity structure with the strongest enhancement effect.Based on this structure,fiber SERS substrate coated with silver nanoparticles was prepared by using the sol self-assembly method and the self-assembly time was controlled to prepare different fiber SERS substrates(Ag/Fiber-x,where x is the self-assembly time 10,20,30,40,50 and 60 minutes).Using 10^(-3)mol·L^(-1)R6G as probe molecule,the Ag/Fiber-x substrate was screened to obtain Ag/Fiber-30 with the strongest enhancement effect.The SERS performances of nano-silver sol and Ag/Fiber-30 substrate were studied by detecting R6G solutions of different concentrations.The experimental results showed that under the same experimental conditions,the detection limits(LOD)of nano-silver sol substrate and Ag/Fiber-30 substrate for R6G are 10-6 and 10-9 mol·L^(-1),respectively.The Raman intensity and concentration of the two substrates were logarithmically transformed and fitted at the Raman shift of 1362 cm^(-1)of Ag/Fiber-30 substrate can reach 0.9753,which was much higher than nano-silver sol substrate.The Raman signal reproducibility test results showed that the RSD values of two substrates at each characteristic peak are within a reasonable range,but the RSD value range of Ag/Fiber-30 substrate was small.The stability test results of two substrates showed that the comprehensive Raman strength of nano-silver sol substrate at 1362 cm-1 decreased by 45.90%after 35 days.The comprehensive Raman strength of Ag/Fiber-30 substrate at 1362 cm-1 decreased by 17.58%after 35 days.These results indicated that the Ag/Fiber-30 substrate has long-term stability.Simultaneously,the relative enhancement factor(REF)of two substrates w

关 键 词：表面增强拉曼散射 纳米银溶胶 光纤 溶胶自组法 罗丹明6G 

分 类 号：TN247[电子电信—物理电子学]