碳量子点的制备及其在荧光分析中的应用研究

发布时间：2018-04-20 14:06

本文选题：碳量子点 + 荧光分析　；参考：《广西大学》2017年硕士论文

【摘要】：碳量子点是近年来碳材料中的新星,它和传统半导体量子点一样拥有纳米级的粒子尺寸、优秀的电子传导能力和极强的荧光,比传统半导体量子点更有生物相容性,更容易实现表面官能化,制备过程更加简单。碳量子点在生物学成像、光催化、太阳能电池和荧光分析领域都已经有所应用,具有比传统半导体量子点更广阔的发展潜力。当前对碳量子点的研究主要集中于N、S单掺或二元共掺碳量子点,对其它掺杂元素和三元共掺碳量子点的研究较少。对包覆碳量子点的制备方法及应用研究不足。缺少简单高效合成荧光可调碳量子点的方法。碳量子点荧光分析目标主要集中于Fe3+和Hg2+,对其它分析目标(尤其是阴离子和中性分子)研究不足,荧光检测机理探讨不够深入。针对上述研究背景,本研究在第三章中,使用水热法制备N、S、P三元共掺碳量子点,再以共掺碳量子点为荧光探针,实现对Eu3+离子的检测。此章节研究的意义在于填补了相关领域内对三元共掺碳量子点的研究的空白,创新性地建立了荧光分析Eu3+离子的检测方法。在第四章中,先制备N掺杂碳量子点,再用对甲基磺憸化环糊精对其进行包覆,制备出β-环糊精包覆的碳量子点;包覆碳量子点的荧光强度会被F-离子增强,基于此原理开发了对F-离子的荧光分析新方法。此章节为包覆碳量子点的制备提供了新思路,拓展了碳量子点在检测阴离子方面的应用,在众多碳量子点检测阳离子的研究中有特殊的意义。在第五章中,以邻苯二胺和正丙醇为原料制备了发射光为黄光的碳量子点;基于黄光碳量子点和金纳米粒子的荧光内滤效应,建立了检测三聚氰胺的新方法。此章节研究的意义在于制备出了较少见的发射光为黄光的碳量子点,为制备荧光可调碳量子点迈出探索性的一步;开发的检测方法体现了荧光内滤原理的灵活运用,对三聚氰胺的检测范围和国标使用的液相色谱法基本一致,具有操作简便、检测成本低等优点。得到的结论有:(1)N、S、P三元共掺碳量子点的平均粒径为20 nm;紫外可见吸收光谱在209 nm和342 nm处有明显的吸收峰,分别对应共轭体系中的π-π*跃迁和表面态能级;X射线光电子能谱证实N、S、P与C都形成了化学键;红外吸收光谱显示碳量子点表面含有丰富的羟基、氨基和C=O、C-N、P-O、C-S结构。共掺碳量子点最大激发波长350 nm,最大发射波长443 nm,发射光为蓝光,半峰宽77 nm,没有基于激发光改变发射光的现象。共掺碳量子点检测Eu3+线性范围为4.878 μmol·L-1到33.33 μmol-L-1,线性方程为△F=10.2C-19.2,相关系数0.998,检出限为0.367μmol·L-1,选择性良好,在模拟废水检测Eu3+中平均回收率103.6%。(2)环糊精包覆碳量子点平均粒径为50 nm;在215 nm处有紫外可见吸收峰,说明含有其含有大量π-π*键;X射线光电子能谱说明β-环糊精通过C-N-C结构与量子点碳骨架相连,形成包覆;红外吸收光谱显示碳量子点表面含有丰富的羟基、氨基和C=O、C=C、C-N、C-O-C等官能团。包覆碳量子点最大激发波长348 nm,最大发射波长462 nm,发射光为蓝光,半峰宽92 nm,有基于激发光改变发射光的现象。检测F-线性范围27.62 μmol·L-1到544.6 μmol·L-1 线性方程为△F=0.383C-1.69,线性相关系数0.998,检出限0.367 μmol·L-1,选择性良好,在检测牙膏中的F-离子实验中平均误差5.8%。(3)黄光碳量子点平均粒径为30 nm;紫外可见吸收峰图谱说明碳量子点含有π-π*键和表面态能级吸收;X射线光电子能谱显示碳量子点含有C、N、O元素;红外吸收光谱说明其表面有丰富的羟基、氨基和C=O、C=C、C-N、C-O-C结构。黄光碳量子点最大激发波长415 nm,最大发射广西大学硕士学位论文碳量子点的制备及其在荧光分析中的应用研究波长556 nm,半峰宽78 nm,发射光为黄光,CIE坐标为(0.45,0.56)。检测三聚氰胺线性范围为50.0 μmol·L-1到700.0 μmol·L-1,线性方程为△F=0.421C-22.3,线性相关系数 0.991,检出限 5.808 μmol·L-1。
[Abstract]:Carbon quantum dots are new stars in carbon materials in recent years. Like the traditional semiconductor quantum dots, they have nanometer particle size, excellent electronic conductivity and strong fluorescence. It is more biocompatible than traditional semiconductor quantum dots. It is easier to realize surface functionalization and the preparation process is simpler. Carbon quantum dots are in biological imaging and light. Catalysis, solar cells and fluorescence analysis have been applied in the field, which has a wider potential than the traditional semiconductor quantum dots. The current research on carbon quantum dots is mainly focused on N, S single doped or two Co doped carbon quantum dots, and less research on other doped elements and three element Co doped points. Preparation of carbon quantum dots coated with carbon quantum dots. Methods and applications are insufficient. Lack of a simple and efficient method to synthesize fluoresceable carbon quantum dots. The target of fluorescence analysis of carbon quantum dots is mainly concentrated on Fe3+ and Hg2+. The study of other analytical targets (especially anions and neutral molecules) is insufficient and the mechanism of fluorescence detection is not deep enough. In this study, the third chapter is in this study. N, S, P three yuan Co doped carbon quantum dots are prepared by hydrothermal method, and then Co doped carbon quantum dots are used as fluorescence probes to detect Eu3+ ions. The significance of this chapter is to fill the gap in the study of three yuan Co doped carbon quantum dots in the related fields, and create a new method for the detection of Eu3+ ions in fluorescein analysis. In the fourth chapter, the first part of the study has been made. The N doped carbon quantum dots were prepared and coated with methyl sulfonated cyclodextrin. The carbon quantum dots coated with beta cyclodextrin were prepared. The fluorescence intensity of the coated carbon quantum dots would be enhanced by the F- ion. Based on this principle, a new method for the fluorescence analysis of F- ions was developed. This chapter provides a new idea for the preparation of carbon quantum dots. The application of carbon quantum dots in the detection of anions is of special significance in the study of cations by many carbon quantum dots. In the fifth chapter, the carbon quantum dots with yellow light emitting light are prepared by using o-phthalamine and propanol as raw materials, and the detection of cyanogen based on the fluorescence internal filtration effect of yellow carbon quantum dots and gold nanoparticles is established. The significance of this chapter is the preparation of a rare carbon quantum dot with yellow light emitting light, which is an exploratory step for the preparation of fluorescence tunable carbon quantum dots. The developed detection method embodies the flexible application of the principle of fluorescence internal filtration, the detection range of melamine and the basic one used by the national standard. The results have the advantages of simple operation and low detection cost. The results are as follows: (1) the average particle size of Co doped carbon quantum dots (N, S, P) is 20 nm, the UV visible absorption spectrum has obvious absorption peaks at 209 nm and 342 nm, corresponding to the pi - PI transition and the surface state energy level in the conjugated system, and the X ray photoelectron spectroscopy confirms that N, S, P and C are all formed. The infrared absorption spectra show that the surface of the carbon quantum dots contains rich hydroxyl, amino and C=O, C-N, P-O, C-S structures. The maximum excitation wavelength of Co doped QDs is 350 nm, the maximum emission wavelength is 443 nm, the emission light is blue light, and the half peak width is 77 nm, and the emission light is not changed based on the excitation luminescence. The co doping carbon quantum dots are used to detect the linear range of Eu3+. 4.878 Mu mol / L-1 to 33.33 mu mol-L-1, the linear equation is delta F=10.2C-19.2, the correlation coefficient is 0.998, the detection limit is 0.367 Mu mol. L-1, the average recovery rate 103.6%. (2) of the simulated wastewater Eu3+ 103.6%. (2) cyclodextrin carbon quantum dots average particle diameter is 50 nm, and the 215 nm has the UV visible absorption peak, indicating that it contains a large number of pi - pi *. The X ray photoelectron spectroscopy shows that the beta cyclodextrin is coated with the carbon skeleton of the quantum dots through the C-N-C structure, and the infrared absorption spectra show that the surface of the carbon quantum dots contains rich hydroxyl, amino and C=O, C=C, C-N, C-O-C and other functional groups. The maximum excitation wavelength of the coated carbon quantum dots is 348 nm, the maximum emission wavelength is 462 nm, the emission light is blue light and half peak. The width of 92 nm is based on the stimulated emission of emission light. The linear range of F- linear range is 27.62 mol. L-1 to 544.6 Mu mol. L-1 linear equation is delta F=0.383C-1.69, the linear correlation coefficient is 0.998, the detection limit is 0.367 u mol. L-1, and the selectivity is good. The average error of the 5.8%. (3) Huang Guangtan quantum dots is 30 in the test of the F- ion test in the toothpaste. Nm; the UV visible absorption peak atlas shows that carbon quantum dots contain pion bond and surface state energy level absorption; X ray photoelectron spectroscopy shows that carbon quantum dots contain C, N, O elements. The infrared absorption spectra indicate that the surface has rich hydroxyl, amino and C=O, C=C, C-N, C-O-C structure. The maximum excitation wavelength of the yellow carbon quantum dots is 415 nm, the largest emission Guangxi University The preparation and application of carbon quantum dots in the master's thesis and its application in fluorescence analysis are 556 nm, half peak width, 78 nm, yellow light and CIE coordinate (0.45,0.56). The linear range of melamine is 50 mu mol. L-1 to 700 mol. L-1, linear equation is delta F= 0.421C-22.3, linear correlation coefficient 0.991, detection limit 5.808 Mu mol L -1.

【学位授予单位】：广西大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：O657.3;O613.71;TB383.1

【参考文献】