Preparation method and application of perovskite type composite oxide catalyst

Abstract

The invention discloses a preparation method and application of a perovskite type composite oxide catalyst. The perovskite type composite oxide catalyst is an A-position substituted perovskite type composite oxide. The structural formula of the catalyst is A1-xA'xBO3, wherein x is larger than 0 and smaller than 1; A is La or Nd element; the A'-position substitution ion is one of Ca, Sr, Ba, Ce and the like; and the B-position ion is one of Mn, Co, Ni, Fe and the like. The preparation method comprises the following steps of: according to a chemical metering ratio, weighing a water-soluble salt which contains the A-position, A'-position and B-position elements; mixing the salt and deionized water to obtain 5 to 20 percent salt solution; adding the solution into a beaker; adding activated carbon of which the mass is 0.1 to 1.5 times of the salt into the solution; completely soaking the activated carbon and standing; heating and stirring the mixture, continuously heating until the water content is completely evaporated, wherein the co-crystallized solid mixture is uniformly carried on the activated carbon, and after drying the mixture, grinding the mixture into powder; and sintering the powder in a muffle furnace, cooling the sintered powder with the furnace to room temperature, and grinding the cooled powder to obtain the powder of the perovskite type composite oxide mixed catalyst. The preparation method is suitable for production; and the electrode activity of the perovskite type catalyst can be greatly improved in a zinc air cell structure.

Description

technical field [0001] The invention belongs to the field of inorganic non-metallic materials, and in particular relates to a preparation method and application of a perovskite-type oxide catalyst. Background technique [0002] Perovskite-type composite oxides generally refer to inorganic non-metallic oxides composed of rare earth or alkaline earth elements and transition elements, which have the same crystal structure as perovskite. Because of their good catalytic performance, the performance in alkaline solution is relatively Stable, resistant to oxidation, high conductivity at room temperature, and low price, it is a promising bifunctional oxygen electrode material, and thus has become a research hotspot in the field of positive electrode materials for zinc-air batteries. [0003] At present, there are many methods for preparing perovskite oxides, including solid-phase sintering, salt decomposition, sol-gel, co-precipitation, and solution spray-freeze-drying, etc. It is ...

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Problems solved by technology

[0003] At present, there are many methods for preparing perovskite-type oxides, including solid-phase sintering, salt decomposition, sol-gel, co-precipitation, and solution spray-freeze-drying, etc. Among them, although the solid-phase sintering method operates Simple, but it is not commonly used because it is difficult to mix the solid substances evenly, which affects the conversion rate and activity of the product; although the product prepared by the sol-gel method has the advantages of high purity, good uniformity, and simple process equipment, the method There are many influencing factors, and the treatment period is long, which is not conducive to large-scale production; the co-precipitation method needs to sinter the precipitate at high temperature and for a long time, which is easy to cause the agglomeration of particles and the reduction of specific surface area; and the solution spray-freeze-drying method is also Because of its harsh preparation conditions and high equipment cost, it is not conducive to production and wide application

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