摘 要：在众多的检测方法之中，电化学分析技术因其突出的优点成为了当前研究的焦点。抗坏血酸作为一种常见的还原剂，广泛地存在于医药、食品中。本论文以氧化石墨和氯金酸为原料，采用溶剂热法将金纳米粒子负载在掺氮石墨烯上，制备掺氮石墨烯-金纳米复合材料。通过SEM和XRD表征技术对掺氮石墨烯-金复合材料进行分析，从而确定复合材料的组成和结构，以此复合材料构建电化学传感器，并用于检测抗坏血酸。电化学实验表明，复合材料对抗坏血酸具有较好的催化活性，能显著降低抗坏血酸的氧化电位，增大氧化峰电流，从而有利于提高传感器的灵敏度。在pH=5的磷酸盐缓冲溶液中，线性伏安扫描显(LSV)示在100~5000M范围内抗坏血酸浓度与峰电流呈现线性关系。92645

毕业论文关键词：掺氮石墨烯-金纳米复合材料、电催化、电化学传感器、抗坏血酸

Abstract: Among the methods for detecting biomolecules, electrochemical technology has attracted more and more attention because of its many outstanding advantages。 Ascorbic acid as a common reducing agent, widely present in medicine and food。 Determing its concentration in these products is of great of importance to health of human beings。 In this paper, nitrogen-doped graphene-Au nanocomposites were prepared by solvothermal method using graphite oxide and chloramic acid as raw materials。 The composition and structure of the nanocomposites were characterized by SEM and XRD to confirm its microstructure and composition。 Based on the as-prepared nitrogen-doped graphene-Au nanocomposites electrochemical sensors were constructed to determine ascorbic acid。 Electrochemical experiments show that this nanocomposite possess excellent catalytic activity towards the oxidation of ascorbic acid。 Both the decrease of oxidation potential and increase of oxidation peak current attribute to the catalytic performance of nitrogen doped graphene-Au nanocomposite。 In PBS buffer(pH=5) the linear range is 100~5000M according to LSV analysis。

Keywords: nitrogen-doped graphene-Au nanocomposite，electrocatalysis, electrochemical sensor, ascorbic acid  源F于K优B尔C论V文N网WwW.youeRw.com 原文+QQ752^018766

目 录

1 前言 3

1。1石墨烯基本性质研究 3

1。1。1石墨烯的结构及性质 3

1。1。2石墨烯的制备 4

1。1。3石墨烯的应用 5

1。2掺氮石墨烯的概述 6

1。3电化学传感器概述 6

1。4纳米复合材料简介 7

1。5抗坏血酸简介 7

2  实验部分 8

2。1 实验试剂 8

2。3 实验步骤 8

2。3。1氧化石墨的制备（Hummers法） 8

2。3。2掺氮石墨烯-金纳米复合材料的制备 9

2。3。3  产品处理 9

2。3。4 玻碳电极的打磨与清洗 9

2。3。5  缓冲溶液的配制与处理 10

3 结果与讨论 10

3。1掺氮石墨烯-金纳米复合材料的合成与表征 10

3。2 掺氮石墨烯—Au纳米复合材料对多巴胺的选择性检测