| Ionic liquids are molten salts that are generally consisted of an organic cation and an inorganic anion or organic cation at room temperature. They not only get rid of easy volatilization and poisonous component of the traditional solvents, but have unique physicochemical properties, such as lower vapor pressure, wider electrochemical windows, good conductivity, special solubility and no pollution. Now ionic liquids become a kind of new green solutions that are friendly to the environment in the 21st century.The wide windows of ionic liquids avoid the interference of hydrogen and oxygen evolution in the aqueous solution. So they are widely used as solution and medium in the electrochemical analysis, but the work in them are focused on the electrochemical behavior of the transition metal ions and heterocyclic compounds, there are few studies about that of aliphatic derivatives, specially the exploration of reaction mechanism and kinetic constants of the active substances in ionic liquids, however, all of these are the important data and theoretical basis of pushing them into industrialization; In addition, preparation of conductive nano-polymer by micro-emulsion is a new method for nano-material, if ionic liquids micro-emulsion are used as solution, they can be diluted into nano or micro particles reactors, so the consumption of them can be saved largely, but the study on this is at an outset stage. In this paper, we discuss the application of ionic liquids in electrochemical analysis and micro-emulsion. The main results obtained in this paper are shown as follows:1 The similar electrochemical oxidation behaviors of hydroxypivalaldehyde in ionic liquids (ILs) medium, C4MIMBF4, C4MIMPF6 and C8MIMPF6, are investigated using classic electrochemical methods, cyclic voltammetry method and coulometric method, respectively. Results show that the electrooxidation of hydroxypivalaldehyde is an irreversible reaction in these ionic liquids, consisting of two successive one-electron reactions at glass carbon (GC) electrode. Only the product, hydroxypivalic acid is detected by high performance liquid chromatography (HPLC); The scan rates and reaction temperature effected on the behaviors of hydroxypivalaldehyde have been studied in this paper, the peak currents increased with the potential scan rates ranging from 0.05 to 0.25 V?s-1 gradually, and the peak potential shifted positively, there is a good linear between the peak currents and square root of scan rates, respectively; The temperature coefficient of the peak currents were less than 2%, this means that the reaction is not controlled by the electrochemical procession, the peak currents increased with the temperature, and the peak potential shifted negatively, there is a good linear between the peak currents and the temperature, respectively; The higher viscosity, the more disadvantageous to the dissolution of active substance, so the dissolution coefficient in [bmim]BF4, [bmim]PF6, and C8MIMPF6 is decreased with the increased viscosity, 8.71×10-7cm2?s-1, 6.66×10-7cm2?s-1, 2.99×10-8cm2?s-1, respectively.2 electrochemical polymerization Aniline is performed by cyclic voltammetry method and chronopotentiometry method in ionic liquid [bmim]PF6 micro-emulsion, which is compared with that obtained in sulfuric acid solution, the results show that not only SO42- doped into polyaniline, but another anion, PF6-; The polymerization circles effected the capacitance of polyaniline film are also discussed by cyclic voltammetry in ionic liquid [bmim]PF6 micro-emulsion, the best circles is 30 and the surface coverage is 5 mg?cm-2, the capacitance of it can get to 950 F?g-1; The micomorphology and the capacitance of polyaniline film obtained using two methods are also compared, the results show that the larger area of polyaniline film using chronopotentiometry method than cyclic voltammetry method, so it is more advantageous to the transmission of the electrons in electrode reaction, the capacitance of polyaniline film get to maximum, 1062 F?g-1 under the suitable polymerization time, 350 s.3 The network morphology of polyaniline/manganese dioxide composite (PANI/MnO2) is prepared by two electro-deposition steps, which is that, as the second level template, PANI film is firstly electrodeposited on the stainless steel electrode, then MnO2 is coated onto the predeposited PANI film. The results of FT-IR, SEM and XRD of the PANI/MnO2 composite indicate that PANI has a good green imine structure and large area; The CV curve with the potential scanning from 0.1 V to 0.8 V proves that the PANI/MnO2 film has a good capacitive property, moreover, the measurement of charge-discharge demonstrated it further and the specific capacitance of this composite is about 658 F·g-1, it can be used as the electrode material for super-capacitor.
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