| Air electrode is one of the important components in zinc-air cell. The main effect factors on performance of air electrode are catalysts oxidation and deoxidization capability and structure of oxygen electrode. Different substitution nanometer perovskite-type catalysts ABO3 are preparation by sol-gel,organic solvent and high energy ball-milling method.In this paper, the optimum conditions of catalyst preparation were found by studying the influences of the sol-gel process parameters on the crystal structure of the nanometer La1-xSrxMnO3, such as the value of pH, the temperature of water bath, the baking temperature of sol. The baking condition of perovskite-type oxide is confirmed by means of DTA-TG. At last, the catalyst with good performance were prepared as follows: mixed the metal ion and citric acid together by molar ratio of 1:2, pH value of 8.0 to prepare the sol; then the water in the sol was vaporized for 5h in water bath at temperature of 70℃, and the gel is dried for 10h at the temperature of 80℃. At last, the catalyst is prepared after roasting the gel for 5h at 700℃. It is verified that the oxide have obvious characteristic diffraction peaks and less impurity by XRD. The crystal particle size of oxide is about 1725nm by FWHM with Scherrer formula.Combined with the investigation of mass transfer on the surface of air electrode, the semi-hydrophobic and porous gas diffusion electrodes were fabricated by use of La0.7Sr0.3MnO3 as catalyst. Then employing Hg/HgO elecreode as reference electrode and nickel foam as counter electrode, a semi-cell model was made. The optimum conditions for air electrode preparation were shown as follows: active carbon which was baked for 15 min in 900℃and acetylene black as carrier for catalyst, bond is 60 mass% PTFE liquor, waterproof layer was used whit PTFE membrane which has pore produced in Beijing Organic Thin film Research Institute, the aperture is 2μm, the thickness is 0.2mm. 10% PTFE in catalysis layer, 30% catalyst in catalysislayer, nickel screen for current collector, compacting pressure 6MPa.The air electrode exhibited good performance that current density was as high as 130.45mA at -0.5V ( Vs Hg/Hg0 ) .The electrode that was prepared with above method can discharge with 100 mA·cm-2 for 12 hours.Preparation craft of organic solvent and high energy ball-milling was also studied in this article, determined the preparation craft of organic solvent that pH is 5.0, milling time is 1.5h. The influence of ball milling time to nanometer perovskite-type catalysts crystal structure was studied, determined the ball-milling time is 15h rotate speed is 300rotate per min. The difference of the catalyzer active which produced by these two methods and sol-gel method was studied.
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