Preparation And Electrocatalytic Properties Of Polyoxometalate-carbon Composite Materials Modified Electrode

Polyoxometalates(POMs) is a class of polyoxometalate compound has a unique structure and excellent chemical and physical properties. Acid has a special multi-step,multi-electron transfer process reversible, and can maintain the same structure, which attracted much attention of researchers, especially in terms of electrocatalytic and catalytic reactions photoelectrocatalytic.As carbon materials having a chemically inert, relatively inexpensive electrically conductive material in electrochemical applications has been widely used. Its excellent electrical characteristics, such as when the modified electrode material, are possible to enhance the electron transfer reactions, thereby improving the efficiency of the reaction, e.g.electrocatalytic reactions.This paper focuses on the POMs, gold nanoparticles and carbon materials modified electrodes and their electrochemical, optical and catalytic properties. The specific contents are summarized as follows:1. Using layer-by-layer self-assembly technique, as the use of electrostatic adsorption between particles, we prepared Dawson type tungsten-phosphate(P2W18), polyallylamine hydrochloride modified carbon nanotubes(p CNTs) and polyethyleneimine wrapped gold nanoparticles(PEI-Au) ternary complex membrane electrode material. The electrochemical tests demonstrate the excellent electrochemical properties of the electrode and the electrode stability, and promote the synergistic effect of the three makes P2W18 / p CNTs /P2W18 / Au composite film electrode in terms of electro-catalytic reduction H2O2 exhibited relatively P2W18/Au and P2W18/p CNTs membrane highest electrocatalytic activity. Using the time to prove that the current method of electro-catalytic reduction of H2O2 electrode fast response, low detection limit.2. The interaction between the ions Dawson type tungsten-phosphate(P2W18), room temperature ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate(Bmim) and multi-walled carbon nanotubes(MWNTs) prepared P2W18/PILs-MWNTs modified electrode. Under acidic and neutral conditions, characterized by cyclic voltammetry electrode good stability P2W18/PILs-MWNTs modification. In addition, the use of time-current curve, P2W18/PILs-MWNTs modified electrode in p H = 7 PBS buffer shows good electrical oxidation activity towards dopamine.3. The electrochemical properties of four different carbon nanomaterials: graphene oxide, chemically reduced graphene oxide, electrochemical reduced graphene oxide andcarbon nanotubes were compared. Use ferricyanide K3[Fe(CN)6] and hexaammineruthenium(III) chloride [Ru(NH3)6]Cl3 as electrochemical probes, they react in different carbon materials modified electrode kinetics studied. From cyclic voltammetry and electrochemical impedance spectroscopy was found ferricyanide probe molecules differ in different electrode surface reaction kinetics, and the probe is calculated on different materials heterogeneous electron transfer constant. The study shows that electronic conduction velocity is closely related to the chemical nature of the surface of the carbon material, such as the C/O rate of the surface, oxygen-containing functional groups, etc.,which provides a theoretical basis for carbon materials in electrochemistry.