Preparation Nanocomposite Chemically Modified Electrodes With Anodic Aluminum Oxide Template And Their Electrochemical And Electrocatalysis Properties Research

Porous anodic aluminum oxide （AAO） consist of high-aspect-ratio nanotubes array,which parallel each other and almost vertical to the surface. The both ends of the nanotubesare open with no across. The size and shape of the nanopores are variable, we can obtaindue nanotubes by changing the parameters of the experiment. The confined nanotubes canbe used to modify nano-materials with different styles. Two-step anodizing process wasused to prepare porous anodic aluminum oxide membranes. Chemically modifiedelectrodes were preparated with AAO templates. We characterized the surface topographyof them with a series of measurements, such as X-ray diffraction （XRD）, ScanningElectron Microscope （SEM）, Atomic Force Microscope （AFM） and solide-ultraviolet （UV）spectrum.We also researched the electrochemical and electrocatalysis properties of theCMEs.Firstly, prussian blue （PB） modified electrode with copper oxide （CuO）-doped wasfabricated by AAO template and electrodeposit method. It was called PB-CuO/AAO/GCCME. We studied the redox mechanism of PB and experimental factor, and conducted theexperiment under optimum condition. The surface topographies of AAO and PB modifiedelectrode were investigated through AFM and SEM. AAO film was composed ofco-continuous networks of hexagonal unit cells, there was one micropore which wasvertical to the aluminous substract in the middle of each cell. The pore was round andabout70nm in size,13μm in thickness. A series of electrochemical properties of H₂O₂onPB-CuO/AAO/GC CME were researched. It performed fast response and high selectivity,it can keep the ionic influence away, such as Ca²⁺，Mg²⁺，NO^3-，Na⁺，SO₄^2-，NH₄⁺.Detectability was9×10^-9M （S/N=3）, linearity ranged from0.933mM to1.73mM,2.0mM to10.7mM, and correlation coefficents were0.990and0.994, respectively. Besideswe studied the recovery of the method, its RSD was1.78%. It was the proof that thetechnique was available. We made tests of practice sample, quanyangquan mineral waterand water for life as an example, good results were obtained.Secondly, AAO with aluminous substrate was used as original electrode toelectrodeposit nano-lead dioxide. By this way, we can avoid the defect that AAO was thinand fragile. XRD and SEM were used to characterize the structures of the PbO₂-AAO/AlCME. β-PbO₂with excellent electrochemical performance was obtained. A series ofelectrocatalysis testings of reducing substances, such as hydrogen peroxide, ascorbic acid,pyrocatechol and so on, were studied on AAO/Al and PbO₂-AAO/Al to examine the electrode. The PbO₂-AAO/Al CME exhibited a remarkably catalytic activity than theformer. It had a fast response, reach stability quickly. Nano-PbO₂was proved to have bettercatalysis on them. Especially for ascorbic acid, hydroquinone and pyrocatechol, it extendedto0.25nM. So we concluded that the nano-PbO₂can not only cling to the chanels of AAOfirmly，but remain reversibility. Electrochemical activity, high sensitivity and good stabilityof the lead dioxide modified electrode were investigated.The method above has the advantages of simple process and low cost. It is aperspective way to fabricated modified electrode with application value in sewagedisposal.