Air Battery Perovskite-type Catalyst And The Electro-catalytic Properties

The development of metal-air battery and air electrode is briefly introduced in this paper. Then, the catalysts for oxygen reduction, especially perovskite-type oxide, are reviewed in detail. Meanwhile, the principle of sol-gel technology is summered, and then their preparation with Sol-Gel method has been briefly introduced. According to reported literature, La1-xA' xCoO3 perovskite-type compound oxide powders with Sol-Gel method is selected.In this experiment, La1-xA ' xCoO3 perovskite-type compound oxide powders are prepared with Sol-Gel method , The experiments were focused on the effects of pH value, calcintion temperature,calcintion time , heat preservation time, the power of microwave and microwave calcinition time on the crystal structure and conductivity.The thermal change of reaction was analyzed by using TG/DTA with increment of the temperature. DSC and TDA analysis of La0.6Ca0.4CoO3 gel indicates the compound oxide powders finish phase transformation bascilly about 680℃. DSC and TDA analysis of La0.6Sr0.4CoO3 powder indicates organic function regiments are resolved at 435℃~867℃ with phase transformation from non-crystal dehydrating to microcrystal structure.Then in terms of these, X-ray diffraction of La1-xCaxCo03gel at 200℃ 'calcine shows only metal oxides and simple metal exist,and no perovskite phases form. And that of La1-x Sr xCoO3 gel shows only metal oxides exist without simple metal and perovskite phases form.The powders of high temperature calcine form the stabler perovskite-type compound oxide powders. During microwave rapid heating process, because of spreading time too short the part of reactional products doesn't transform to the thermodynamic stabilized structures very well. The calcine's crystal phases are much more complicated and the transitional phases appear during calcine process.The structure of crystal was checked through X-ray diffraction. Finally, the catalyst powders were added to air electrode and their catalyzing properties were examined with the chemistry work station. The results show that pH value effects on crystal structures of the powders are not very obvious; When the microwave calcining time is longer ,the main phase in catalyst is perovskite-type matter with minor other phases. The catalysis of the powders calcined at 9 min in microwave stove is the best. The higher temperature of calcining, the better powders'crystallization , the electricity conductivity was decreased.The powders' catalysis calcined at 800℃ in electric stove is the best.The catalysis and crystallization of the powers calcined in microwave stove is better than those of the powders calcined in electric stove. The catalyzing property of LaSrCoO3 is better than LaCaCoO3.