Electrochemical Sensing Platform Based on the Highly Ordered Mesoporous Carbon-Fullerene System

摘要

In this paper, we report a novel all-carbon two-dimensionally ordered nanocomposite electrode system on the basis of the consideration of host-guest chemistry, which utilizes synergistic interactions between a nanostructured matrix of ordered mesoporous carbon (OMC) and an excellent electron acceptor of nanosized fullerene (C_(60)) to facilitate heterogeneous electron-transfer processes. The integration of OMC-C_(60) by covalent interaction, especially its electrochemical applications for electrocatalysis, has not been explored thus far. Such integration may even appear to be counterintuitive because OMC and C_(60) provide opposite electrochemical benefits in terms of facilitating heterogeneous electron-transfer processes. Nevertheless, the present work demonstrates the integration of OMC and C_(60) can provide a remarkable synergistic augmentation of the current. To illuminate the concept, eight kinds of inorganic and organic electroactive compounds were employed to study the electrochemical response at an OMC-C_(60) modified glassy carbon (OMC-C_(60)/GC) electrode for the first time, which shows more favorable electron-transfer kinetics than OMC/GC, carbon nanotube modified GC, C_(60)/GC, and GC electrodes. Such electrocatalytic behavior at OMC-C_(60)/GC electrode could be attributed to the unique physicochemical properties of OMC and C_(60), especially the unusual host-guest synergy of OMC-C_(60), which induced a substantial decrease in the overvoltage for NADH oxidation compared with GC electrode. The ability of OMC-C_(60) to promote electron transfer not only suggests a new platform for the development of dehydrogenase-based bioelectrochemical devices but also indicates a potential of OMC-C_(60) to be of a wide range of sensing applications because the electrocatalysis of different electroactive compounds at the OMC-C_(60)/GC electrode in this work should be a good model for constructing a novel and promising electrochemical sensing platform for further electrochemical detection of other biomolecules.