原子厚度石墨烯电极和石墨烯导电膜的构建及其生物电化学应用研究

Graphene has a unique atom-thick two-dimensional structure and excellent properties, making it attractive for a variety of electrochemical applications, including electrosynthesis, electrochemical sensors or electrocatalysis, and energy conversion and storage.Electrodes of nanometer sizes provide a model approach to study the nanoscale electrochemical properties and processes, which are of fundamental and applied significance in a variety of areas including energy and environmental science, scanning probe microscopies, nanofabrication as well as electrochemistry itself.The past three decades have seen tremendous grouth and in creased application of nanoelectrodes in fundamental electrochemistry, electrochemical analysis, electrocatalysis,and many other research areas. Nanoelectrodes can be considered a special type of ultramicroelectrode with samller critical dimensions. In this project, the atom-thick graphene electrode will be fabricated at first. And as the graphene edge consisting of one-atom thick defective graphitic line of carbon atoms with dandling bonds and variou cappine moieties (e.g., hydrogen, hydroxyl, carbonyl and carboxyl groups), it is possible to modify the edge with functional groups through covalent bonding or other methods. The functionalized graphene can also be used to prepare electrode in one-atom thick. As a resut, the thinnest ultrananoelectrode in the world will be obtained, which can be exploited to study its voltammetry behavior and its sensing effects towards biomolecules in atom dimension.On the other hand, the same atom-thick graphene sheet will be used to fabricte conductive film as well as functionalized grahpene conductive films similar to ITO. The electrochemical behavior and biosensing effect of the graphene conductive film will be explored. Thus the electrochemical behavior and biosensing effect of atom-thick graphene will be studied both in microscopic and macroscopic dimensions, which might promote the applicaions of graphene in bioelectrochemistry area.

石墨烯因其奇特的单碳原子层厚度二维结构和优异的性能，在电化学领域如电电合成、化学传感器/电催化、能量转化与存贮等方面引起广泛关注；纳米电极近年来在电化学、电催化等研究领域的应用得到迅猛发展。本项目一方面计划制备单原子厚度的石墨烯电极，同时利用石墨烯边缘的缺陷和基团，通过共价、非共价等方法修饰上特定功能的分子，使石墨烯的某些性质发生改变，进而制备功能化的单原子厚度石墨电极，得到世界上最薄的超纳米电极，并以此开展原子尺度纳米电极的伏安特性及其对多种生物分子的传感作用研究。另一方面，利用同样的原子厚度石墨烯片制备类似于ITO的导电薄膜，并通过石墨烯功能化制备多种不同功能化的石墨烯导电膜，利用各种物理手段对导电膜电极进行表征，研究其本身的电化学性质及对多种生物分子的传感作用。这样从微观和宏观两种尺度来研究原子厚度石墨烯的电化学性质和生物传感作用，从而进一步开发石墨烯在生物电化学领域的应用。

石墨烯因其比表面积大、电子转移速率快、电化学稳定性高等优点，而被广泛的应用到生物电化学领域。化学气相沉积（CVD）法制备的石墨烯除了具有优良的电化学性能外，还具有结构缺陷少、可大面积制备、 层数可控等特性, 引起众多研究者的广泛关注。CVD石墨烯边缘和面都具有优异的电化学性能。本项目一方面利用CVD石墨烯的边缘制备了原子厚度级的纳米电极，在其上修饰铜纳米颗粒，并将其应用于葡萄糖的传感作用，得到了产，高效灵敏的无酶葡萄糖传感器。另一方面利用CVD石墨烯的面制备柔性石墨烯平面电极(GPE)，然后在其表面分别修饰金纳米颗粒、铁氰化钴(CoHCF)纳米颗粒、L-半胱氨酸、咖啡酸等，并应用于多巴胺、抗坏血酸、肾上腺素、NADH、过氧化氢等生物分子的传感作用。GPE传感器具有检出限低、检测灵敏快捷、稳定性好、抗干扰能力强、制作成本低、制备过程简单等优点。