Studies On Electrochemical Behaviors Of Ordered Mesoporous Carbon Modified Electrode Influenced By The Pore Characteristics And Composition

In recent years, there has been considerable interest in a novel material, i.e., ordered mesoporous carbon (OMC), which was first synthesized in 1999. OMC could be promising candidates for catalyst supports, adsorbents, energy storage media especially because of its admirable properties, such as extremely high specific surface area, large pore volume as well as electrical conductivity. Contrary to most porous silica-based materials that are electronic insulators, the mesoporous carbons are intrinsically conductors and easy to synthesize. Hence, more and more attention was focused on the electrochemistry and electrocatalysis of OMC and the composite materials as advanced electrode materialsThree samples of ordered mesoporous carbon (OMC-x) materials with different pore characteristics were prepared by templating SBA-15 mesoporous silica materials. The pore characteristics of the obtained OMC-x materials were easily controlled by varying the sucrose to silica weight ratio (x) of 0.6, 1.25 and 3 in the synthesis process. OMC-0.6, OMC-1.25 and OMC-3 were characterized by X-ray diffraction (XRD), nitrogen adsorption-desorption isotherm and Raman spectroscopy. The electrochemical behaviors of hydroquinone (HQ) were studied at OMC-x/GC electrode for the first time, which all exhibit strong electrocatalytic response. So the electrocatalytic oxidation of HQ is investigated at OMC-0.6/GC electrode in detail. The results show that OMC-0.6/GC electrode could be a promising candidate for effectively electrochemical sensors for the detection of HQ due to its very low detection limit (0.3 nmol L-1) and fast response.Additionally, ordered mesoporous cobalt oxide/carbon nanocomposite (OMC-Co) was synthesized by templating SBA-15 mesoporous silica materials and thermolysis. Stable suspension was obtained by dispersing the OMC and functionalized OMC in a solution of Nafion. By coating the suspension onto the GC electrode, OMC/GC and OMC-Co/GC electrode were prepared and characterized. The comparison of electrocatalytic performances towards glutathione (GSH) was carried out at GC, Nafion/GC, OMC/GC and OMC-Co/GC electrodes in pH 3.98 PBS through Cyclic Voltammetry (CV). Compared with GC and Nafion/GC electrode, OMC/GC and OMC-Co/GC electrode exhibit strong electrocatalytic response toward GSH. The anodic peak current of GSH at OMC-Co/GC electrode increased obviously and was almost 4.2 times of that at OMC/GC electrode. Furthermore, the GSH response of the OMC-Co/GC electrode at pH 3.98 is extremely stable.