多孔结构薄膜构筑贵金属SERS活性基底

发布时间：2018-05-17 08:32

本文选题：呼吸图技术 + 蜂窝状多孔薄膜　；参考：《江苏科技大学》2017年硕士论文

【摘要】：表面增强拉曼散射作为一种独特的光谱检测技术,自发现以来便在检测极微量小分子方面发挥了极大的作用。因此,被逐渐应用到环境监测、食品安全、医疗健康、光电传感器等诸多领域。众所周知,活性基底的制备是获得SERS(Surface Enhanced Raman Scattering)信号的前提,为了使SERS技术更好地应用于定量分析,所制备的SERS基底应具有增强能力强且均一性好、易于制备和存储、使用方便等优点。因此,SERS活性基底的制备方法尤为重要。国内外研究者在SERS活性基底的制备及其表面增强拉曼性能的研究方面已开展了大量的工作并取得了较大的进展,但是仍缺乏成本低廉、均匀、稳定、重复性好、增强能力强的通用SERS活性基底。基于现状,本文以蜂窝状多孔结构薄膜为模板,制备Au、Au-Ag、Ag纳米颗粒薄膜,并对其SERS性能进行系统研究。本论文主要研究结果如下:(1)采用静态呼吸图方法,制备聚苯乙烯-嵌段-聚(4-乙烯基)吡啶(PS-b-P4VP)蜂窝状多孔结构薄膜。研究溶剂、聚合物浓度、分子量对蜂窝状多孔结构薄膜形成的影响。结果表明:对于PS(122k)-b-P4VP(22k),以CHCl3为溶剂,当聚合物溶液浓度为30 mg/m L时所形成的蜂窝状多孔薄膜具备规整且孔径均一的有序结构,孔径约为2.87μm。浓度偏高或者偏低都会形成不规整的孔结构。三种不同嵌段比的嵌段共聚物中,当嵌段比为5:1时,获得的多孔结构薄膜的有序性最佳。以CS2为溶剂时,PS(122k)-b-P4VP(22k)的浓度为10~ mg/mL时即可形成规整结构的多孔薄膜,但孔径较大,约为4.27μm,随着浓度的不断增加,孔结构逐渐消失。(2)上述蜂窝状多孔结构薄膜经处理后作为模板,结合光化学还原途径制备Au纳米颗粒薄膜。HAuCl_4溶液浓度为0.025 mol/L(V水:V乙醇=1:1),紫外灯光照3 h的条件下所制备的Au纳米颗粒薄膜作为SERS活性基底具备最佳的SERS性能,对R6G(罗丹明6G)分子的增强因子可达6.50×10~6,其检测极限低达10~-8 mol/L,对CV(结晶紫)分子也具有良好的SERS增强效果,增强因子达6.03×10~4。(3)以上述制备的Au纳米颗粒薄膜作为模板,同样采用光化学还原途径制备Au-Ag纳米颗粒薄膜。AgNO_3溶液(V水:V乙醇=1:1)浓度为0.05 mol/L,紫外灯光照2 h的条件下所制备的Au-Ag纳米颗粒薄膜作为SERS活性基底具备最佳的SERS性能,对R6G分子的增强因子可达1.05×10~7,其检测极限低达10~-9mol/L,对CV分子的增强因子达2.41×10~6。并且该基底具备良好的稳定性,其拉曼信号的RSD(相对标准偏差)低于20%。(4)采用类似的方法制备Ag纳米颗粒阵列薄膜。Ag NO_3溶液浓度为0.05 mol/L(V_水:V_乙醇=1:1),紫外灯光照3 h的条件下所制备的Ag纳米颗粒阵列薄膜作为SERS活性基底具备最佳的SERS性能,对R6G分子的增强因子可达1.31×10~9,其检测极限低达10~-10~mol/L。对CV分子的增强因子达8.46×10~5。另外,相比较而言,Ag纳米颗粒阵列薄膜以浸泡方式吸附R6G具有更好的稳定性,其拉曼信号的RSD低于13%。
[Abstract]:Surface enhanced Raman scattering (SERS), as a unique spectral detection technique, has played an important role in the detection of very small molecules since it was discovered. Therefore, it has been gradually applied to many fields, such as environmental monitoring, food safety, medical health, photoelectric sensors and so on. It is well known that the preparation of active substrates is the prerequisite for obtaining SERS(Surface Enhanced Raman Scattering) signals. In order to make the SERS technology more suitable for quantitative analysis, the prepared SERS substrates should have strong enhancement and good uniformity, and be easy to prepare and store. Advantages such as ease of use. Therefore, the preparation method of SERS active substrate is particularly important. Researchers at home and abroad have carried out a lot of work and made great progress in the preparation of SERS active substrates and their surface-enhanced Raman properties, but there is still a lack of low cost, uniform, stable and reproducible. Enhanced ability of the universal SERS active substrate. Based on the present situation, Au-Ag-Ag nano-particle films were prepared by using honeycomb porous films as templates, and their SERS properties were systematically studied. The main results of this thesis are as follows: (1) the honeycomb porous structure films of polystyrene-block poly (4-vinylpyridine) pyridine (PS-b-P4VP) were prepared by using static respiration method. The effects of solvent, polymer concentration and molecular weight on the formation of honeycomb porous films were studied. The results show that the honeycomb porous films formed by using CHCl3 as solvent and the concentration of polymer solution at 30 mg/m L have regular ordered structure and uniform pore size, and the pore size is about 2.87 渭 m. An irregular pore structure is formed when the concentration is on the high side or on the low side. Among the three kinds of block copolymers with different block ratios, when the block ratio is 5:1, the order of porous films is the best. When CS2 was used as solvent, the porous films with regular structure could be formed at the concentration of 10 ~ mg/mL, but the pore size was larger, about 4.27 渭 m. With the increasing of the concentration, the pore structure gradually disappeared. Au nanocrystalline thin films were prepared by photochemical reduction method. The solution concentration of 0.025 mol/L(V water: v ethanol was 1: 1. The au nanocrystalline films were prepared by UV lamp irradiation for 3 h. The au nanoparticles films were prepared as SERS active substrates with the best SERS properties. The enhancement factor of R6G (Rhodamine 6G) molecule is 6.50 脳 10 ~ (-6), the detection limit is 10 ~ (-8) mol / L, and the enhancement factor is 6.03 脳 10 ~ (4) C ~ (-3). The au nanocrystalline film prepared above is used as a template, and the enhancement factor is 6.03 脳 10 ~ (4) C ~ (-1), and the detection limit is 10 ~ (-8) mol 路L ~ (-1). Au-Ag nanoparticles thin films were prepared by photochemical reduction method. The concentration of Au-Ag nanoparticles was 0.05 mol / L in aqueous solution V: v ethanol: 1: 1. The Au-Ag nanocrystalline films prepared by UV lamp irradiation for 2 h had the best SERS properties as active SERS substrates. The enhancement factor for R6G molecule is 1.05 脳 10 ~ (7), the detection limit is 10 ~ (-9) mol / L, and the enhancement factor for CV molecule is 2.41 脳 10 ~ (6) mol 路L ~ (-1). And the substrate has good stability, The RSDs (relative standard deviation) of the Raman signal is lower than 20. 4) the Ag nanoparticles array films were prepared by a similar method. The concentration of Ag NO_3 solution was 0. 05 mol / L water: v _ ethanol 1: 1 and UV lamp illumination for 3 h. The Ag nanoparticles array was prepared under the condition of 0. 05 mol 路L ~ (-1) 路L ~ (-1) V _ (1) O _ (2) O _ (1) O _ 2 solution. The column films have the best SERS properties as SERS active substrates. The enhancement factor of R6G molecule can reach 1.31 脳 10 ~ (9), and its detection limit is 10 ~ 10 ~ (-1) mol 路L ~ (-1). The enhancement factor of CV molecule is 8.46 脳 10 ~ (5). In addition, the adsorption of R6G on Ag nanocrystalline array films by immersion has better stability, and the RSD of Raman signal is lower than 13%.
【学位授予单位】：江苏科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：O657.37

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