氮掺杂石墨烯基金属硫化物复合材料生物电化学传感的研究

发布时间：2018-05-10 11:10

本文选题：氮掺杂石墨烯 + 硫化物　；参考：《安徽工业大学》2017年硕士论文

【摘要】：无酶修饰电极传感器因其成本低、选择性好、灵敏度高、检测范围宽等特点在生物电化学传感器中成为近年来结合多学科且相互渗透的一项新兴科技。葡萄糖、过氧化氢和亚硝酸盐在医药和食品领域中是重要的分析检测物。因此,采用新型的材料构筑无酶电化学生物传感器实现快速准确检测其浓度成为研究热点。自2004年发现机械剥离的石墨烯以来,因具有大的比表面积、高的导热系数和快的载流子迁移率等优良性质,而在各个领域的应用得到了广泛地研究。但因其反应活性低,在电化学领域的应用受到局限。为了提高其电学性质,对其进行化学掺杂成为当前有效的无机化学方法。其中,氮掺杂石墨烯(N-graphene)因氮原子具有强失电子能力,能在碳原子周围产生缺陷,提高了石墨烯的电催化活性而被进一步研究。本论文旨在运用N-graphene与硫基金属纳米材料进行复合,合成出一系列的N-graphene基纳米复合材料,通过它们之间的协同作用提高其对葡萄糖、过氧化氢和亚硝酸盐的电催化效果。论文主要内容包括以下四方面:1.采用溶剂热法探索合成了N-graphene与CoS_2纳米材料形成的复合物,并对CoS_2/N-graphene复合纳米材料修饰电极构筑无酶葡萄糖传感器进行研究。结果表明,与裸玻碳电极、N-graphene以及单一CoS_2纳米材料修饰电极相比,CoS_2/N-graphene复合材料修饰电极对葡萄糖表现出最好的电催化效果,葡萄糖浓度在4μM~5.536 m M之间与其氧化峰电流呈良好的线性关系,灵敏度为421.75μA·m M~(-1)cm~(-2),检出限达1.3μM。表明CoS_2/N-graphene复合材料充分发挥了各自单一材料的协同作用,从而对葡萄糖分子表现出显著的催化活性。并且CoS_2/N-graphene复合材料修饰电极拥有良好的选择性、稳定性和重复性。这些优越性能表明该复合材料有望发展成为在线检测葡萄糖的电化学传感器。2.探索合成了以粒子状组成的海绵型的Co_4S_3纳米材料,并将其与N-graphene结合形成纳米复合材料。研究了H_2O_2分子在该复合材料修饰电极上的电化学响应。结果表明,与裸玻碳电极以及单一Co_4S_3材料修饰电极相比,Co_4S_3/N-graphene复合材料修饰电极对H_2O_2的电催化作用最强。运用安培法研究了Co_4S_3/N-graphene复合材料修饰电极对H_2O_2无酶传感的线性范围为:1μM~2.18 m M,检测限为0.29μM,灵敏度为65.63μA/m M,响应时间为2 s。3.实验中采用溶剂热法合成Ni S/N-graphene复合材料,构筑成葡萄糖无酶电化学传感器后,通过环境友好的方式可靠、简便地无酶化检测葡萄糖。Ni S/N-graphene复合材料具有大的比表面积,并可作为电子传递介质,促进了电极和葡萄糖之间的电荷转移,从而对葡萄糖的氧化表现出较强的电催化作用。当葡萄糖的浓度由5μM增至1.475 m M时安培响应曲线成线性增加。Ni S/N-graphene表现出来的宽的线性范围、低的检测限(1.7μM,S/N=3)、高的灵敏度(60.51μA·m M~(-1))和良好的选择性等特点,为电化学传感提供了一个良好的平台。4.采用乙醇作溶剂合成了Cu S纳米材料和Cu S/N-graphene纳米复合材料,并对其进行必要的物相分析、形貌分析以及元素分析。采用循环伏安法探究Cu S/N-graphene纳米复合材料对亚硝酸盐的电催化效果。实验结果表明,Cu S/N-graphene纳米复合材料相对于Cu S纳米材料的修饰电极,对亚硝酸盐的氧化催化效果更强,氧化峰电流更高,氧化峰电位明显负移。优化各种实验条件后发现,亚硝酸盐浓度在1μM~14.014 m M之间与其氧化峰电流呈良好的线性关系,检出限达0.33μM。该复合材料修饰电极不受常见共存组分的干扰,并且重现性好,电极稳定周期长,成功用于检测实际样品中的亚硝酸盐。
[Abstract]:With low cost, good selectivity, high sensitivity and wide detection range, the non enzyme modified electrode sensor has become a new technology combining multidisciplinary and permeable in biosensors in recent years. Glucose, hydrogen peroxide and nitrite are important analytical agents in the field of medicine and food. Therefore, new methods are used in the field of Medicine and food. The rapid and accurate detection of its concentration has become a hot spot in the construction of an enzyme free electrochemical biosensor. Since the mechanical peeling of graphene in 2004, it has been widely studied in various fields because of its high specific surface area, high thermal conductivity and fast carrier mobility. In order to improve its electrical properties, chemical doping has become an effective inorganic chemical method in order to improve its electrical properties. In addition, nitrogen doped graphene (N-graphene) can produce defects around carbon atoms because of the strong electron loss ability of nitrogen atoms and improve the electrocatalytic activity of graphene. The purpose of this paper is to synthesize a series of N-graphene based nanocomposites by combining N-graphene with sulfur based metal nanomaterials, and to improve the electrocatalytic effect on glucose, hydrogen peroxide and nitrite by their synergism. The main contents of the thesis include the following four aspects: 1. the use of solvent heat The synthesis of N-graphene and CoS_2 nanocomposites was explored and the enzyme free glucose sensor was constructed on the CoS_2/N-graphene composite nanomaterial modified electrode. The results showed that the CoS_2/N-graphene composite modified electrode was compared with the naked glassy carbon electrode, N-graphene and the single CoS_2 Nanomaterial Modified electrode. The glucose showed the best electrocatalytic effect. The glucose concentration had a good linear relationship with the peak current of 4 M~5.536 m M, and the sensitivity was 421.75 A. M M~ (-1) cm~ (-2). The detection limit was 1.3 micron M. indicating that CoS_2/N-graphene composites fully played the synergistic effect of each single material, thus showing the glucose molecules. Significant catalytic activity. And the CoS_2/N-graphene composite modified electrode has good selectivity, stability and repeatability. These properties show that the composite is expected to develop into an electrochemical sensor for on-line detection of glucose and.2. to explore the synthesis of a particle like spongy Co_4S_3 nanomaterial, and N- The electrochemical response of H_2O_2 molecules on this composite modified electrode was studied by graphene. The results showed that the electrocatalysis of Co_4S_3/N-graphene composite modified electrode was the strongest compared with bare glassy carbon electrode and single Co_4S_3 modified electrode. Co_4S_3/N-gr was used to study Co_4S_3/N-gr by amperometric method. The linear range of the aphene composite modified electrode for H_2O_2 free enzyme sensing is 1 mu M~2.18 m M, the detection limit is 0.29 mu M, the sensitivity is 65.63 mu A/m M, and the response time is 2 s.3. experiment by solvent thermal synthesis of Ni S/N-graphene composite material, and after constructing the glucose free enzyme electrochemical sensor, it is reliable and simple by environmentally friendly way. The non enzymatic detection of glucose.Ni S/N-graphene composite has a large specific surface area, and can be used as an electron transfer medium, promoting the charge transfer between the electrode and glucose, thus showing a strong electrocatalytic effect on the oxidation of glucose. When the glucose concentration is increased from 5 to 1.475 m M, the ampere response curve is linearly increased. With the wide linear range, low detection limit (1.7, M, S/N=3), high sensitivity (60.51 A, m M~ (-1)) and good selectivity,.Ni S/N-graphene provides a good platform for electrochemical sensing with ethanol as solvent to synthesize Cu S nanomaterials and Cu nanocomposites. The necessary phase analysis, morphology analysis and elemental analysis are used to investigate the electrocatalytic effect of Cu S/N-graphene nanocomposites on nitrite by cyclic voltammetry. The experimental results show that the oxidation catalytic effect of Cu S/N-graphene nanocomposites is stronger than the modified electrode of Cu S nanomaterials, and the peak current of oxidation peak is higher. Higher oxidation peak potential is obviously negative. After optimizing the experimental conditions, it is found that the concentration of nitrite in 1 M~14.014 m M has a good linear relationship with the peak current of oxidation peak, and the detection limit is 0.33 M.. The composite modified electrode is not disturbed by common coexisting components, and it is highly repeatable, and the electrode has a long stable period and is successfully used for detection. Nitrite in the actual sample.

【学位授予单位】：安徽工业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：O657.1;TB332

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