大尺寸石墨烯量子点组装体的制备及电化学发光性能

对氧化石墨烯纳米材料进行HNO₃氧化处理, 制备了水溶性好且具有强电化学发光(ECL)活性的大尺寸石墨烯量子点组装体(Large-sized graphene quantum dot assemblies, LSGQD-NAs). 利用透射电子显微镜(TEM)、 原子力显微镜(AFM)、 傅里叶变换红外光谱(FTIR)和拉曼光谱(Raman)等方法对其进行了表征, 结果表明, 石墨烯量子点组装体的平均高度为20 nm, 且富含大量的羟基和羧基. 电化学测试结果显示, 在共反应物K₂S₂O₈存在下, LSGQD-NAs在阴极产生很强的ECL(峰值约在685 nm); 并推测了其ECL反应机理, 发现LSGQD-NAs容易通过中心未氧化的石墨烯π-π作用于GC电极表面进行组装修饰. 本研究为基于石墨烯量子点ECL传感器的研究提供了新方法.

Fabrication of a Dispersible Large-sized Graphene Quantum Dot Assemblies from Graphene Oxide and Its Electrogenerated Chemiluminescence Behaviors

A dispersible large-sized graphene quantum dots assemblies（LSGQD-NAs） in aqueous solution with strong electrochemiluminescence activity was fabricated from graphene oxide by nitric acid etching. LSGQD-NAs were characterized by transmission electron microscopy（TEM）， atomic force microscopy（AFM）， Fourier transform infrared spectroscopy（FTIR） and Raman spectroscopy（Raman）， etc. The results demonstrated that the large-sized graphene quantum dots had an average height of 20 nm and contained abundant carboxyl and hydroxyl groups. Strong ECL was studied in detail with the coreaction of K₂S₂O₈ and the maximum emission wavelength at 685 nm. It is found that LSGQD-NAs can be easily assembled and modified on the surface of GC electrode through the π?π bond action of unoxidized graphene. This study provides a new method for the research of ECL sensor based on graphene quantum dots.