碳纳米管/石墨烯垂直阵列伏安传感器的设计与应用研究

Carbon nanotubes/graphene modified electrodes as voltammetric sensors are widely used in electroanalytical chemistry. In current modifying methods, carbon nanotubes/graphene were disordered or modified less at the electrode surface, on which the high electrochemical activity and catalytic properties of carbon nanotubes and graphene will be diaplayed full. This project proposes that the carbon nanotubes/graphene will be vertically and tightly modified on the electrode surface, which is fabricated as carbon nanotubes/graphene array voltammetric sensor. Firstly, some functional groups are grafted on one end of carbon nanotubes and one side of graphene, which make them suitable for fabricating LB film. Then, the functional carbon nanotubes and graphene will be modified on electrode using LB membrane technology. For this fabrication, the carbon nanotubes and graphene will be ordered monolayer and the tube bodies and graphene sheets will be perpendicular to the electrode surface, i.e. carbon nanotubes/graphene array voltammetric sensor. These array sensors will display full the electrochemical activity and electrocatalytic properties of carbon nanotubes and graphene, achieving the goal of improving the electron transport rate and detection sensitivity for the studied substances. By using the big specific surface area and biocompatibility of carbon nanotubes and graphene, enzyme and protein biomacromolecules will be immobilized into the functionalized carbon nanotubes/graphene LB film, constructing the third generation electrochemical biosensors. Under the LB film micro-environment, the electrochemical behavior and activity change rule of biomacromolecules will be studied.

碳纳米管/石墨烯用于修饰电极作为伏安传感器在电分析中已广泛应用，在现行修饰方法中，碳纳米管/石墨烯在电极表面排列无序或修饰量较少，未能充分发挥碳纳米管/石墨烯高的电化学活性和电催化性能。项目提出将碳纳米管/石墨烯垂直紧密排列修饰在电极表面，制作成碳纳米管/石墨烯阵列的伏安传感器。首先在碳纳米管的一端和石墨烯的一边嫁接上适合制作LB膜的功能基团，然后借助LB膜技术将其修饰在电极上，这样制作的修饰电极，碳纳米管/石墨烯将整齐地单层排列，碳纳米管管体和石墨烯片体将垂直于电极表面，即碳纳米管/石墨烯阵列伏安传感器，充分发挥碳纳米管/石墨烯的高电化学活性和电催化性能，提高研究底物的电子传递速率和检测灵敏度。利用碳纳米管/石墨烯大比表面积和生物相容性，将酶、蛋白质等生物大分子固定于功能化的碳纳米管/石墨烯LB膜中，构建第三代生物电化学传感器，研究在LB膜微环境下，生物大分子的电化学行为及活性变化规律。

项目研究的主旨是要制备碳纳米管/石墨烯有序排列（阵列）修饰电极，制备一类新型伏安传感器，充分发挥碳纳米管/石墨烯的电子传导沿轴/片方向速率快的优势，以提高电化学检测的灵敏度，拓宽其在电分析化学中的应用。研究一直围绕既定计划进行，共研究制备了三类新型伏安传感器：①利用气相沉积技术，合成了阵列的多壁碳纳米管；借助于LB膜技术，制备了单壁和多壁碳纳米管阵列修饰电极，研究结果表明，其作为伏安传感器，具有更高的灵敏度，充分发挥了碳纳米管沿轴向电荷传导速率快的优势。②石墨烯阵列修饰电极的工作是通过电流脉冲还原氧化石墨烯实现的，氧化石墨烯配制成水溶性悬浊液，利用脉冲电流将氧化石墨烯还原的同时，在玻碳电极表面沉积，并形成具有一定趋向的石墨烯片，制备的传感器很高的灵敏度。③利用不同的功能团将碳纳米管/石墨烯修饰，合成出功能化的碳纳米管/石墨烯纳米材料，增强碳纳米管/石墨烯的电子传导速率，进而修饰在电极表明制备一类新的伏安传感器。上述三类新型伏安传感器分别应用于44种物质的电化学研究，包括生物分子、药物分子、中药活性成分、农药残留和环境污染物。分别研究了它们的电化学性质，建立了灵敏可靠的电分析方法。研究成果共发表SCI论文50篇，拓宽了碳纳米管/石墨烯在电分析化学领域的应用范围，也为碳纳米管石墨烯在其它领域的应用提供了新的思路。