Method for preparing conductive powder by recoating aluminum-doped nano zinc oxide with aluminum

Abstract

The invention discloses a method for preparing conductive powder by recoating aluminum-doped nano zinc oxide with aluminum. The method comprises the following steps: firstly, preparing aluminum-doped zinc oxide powder; secondly, coating the aluminum-doped zinc oxide powder with an aluminum-containing film; finally, mixing the coated aluminum-doped zinc oxide powder with zinc powder, grinding, and calcining in an inert gas atmosphere to obtain the conductive powder. The method has the advantages that the zinc oxide conductive powder is prepared through primary aluminum doping and secondary aluminum coating, the primary aluminum doping improves the whiteness and the water dispersion of the nano zinc oxide and reduces the particle size of the nano zinc oxide, and the secondary aluminum coating further increases the defect concentration of zinc oxide crystals and improves the conductivity of the nano zinc oxide; the aluminum-doped zinc oxide is coated with a thin oxide film, so that zinc ions in water are unlikely to dissolve out, and the ball milling process of the zinc powder and the aluminum-doped zinc oxide is facilitated; the prepared conductive powder is high in conductive ability, small in particle size, light in color, wide in sources of raw materials, low in production cost, simple in preparation method, high in security, relatively light in environmental pollution, and suitable for industrial mass production.

Description

technical field [0001] The invention relates to a preparation method of an aluminum-doped nano-zinc oxide conductive powder, in particular to a preparation method of an aluminum-doped nano-zinc oxide heavy-coated aluminum conductive powder. Background technique [0002] Conductive powder mainly includes: ① metal powder such as gold, silver, copper, iron, nickel, etc., but because it is unstable in the air and easy to oxidize, its density is easy to deposit, which seriously affects its conductivity, so metal powder is gradually Replaced by emerging conductive powders; ②Carbon-based powders such as graphite, carbon black, etc., have better electrical conductivity, but because of their inherent blackness, their application range is greatly limited; ③Metal oxides such as tin oxide, oxide Antimony, indium oxide, tin-doped indium oxide (ITO), antimony-doped tin oxide (ATO), gallium-doped zinc oxide (ZGO), etc. Among them, the compounds for preparing tin oxide and antimony oxide ha...

AI Technical Summary

Problems solved by technology

[0002] Conductive powder mainly includes: ① metal powder such as gold, silver, copper, iron, nickel, etc., but because it is unstable in the air and easy to oxidize, its density is easy to deposit, which seriously affects its conductivity, so metal powder is gradually Replaced by emerging conductive powders; ②Carbon-based powders such as graphite, carbon black, etc., have better electrical conductivity, but because of their inherent blackness, their application range is greatly limited; ③Metal oxides such as tin oxide, oxide Antimony, indium oxide, tin-doped indium oxide (ITO), antimony-doped tin oxide (ATO), gallium-doped zinc oxide (ZGO), etc. Among them, the compounds for preparing tin oxide and antimony oxide have high or low toxicity , and ATO has blue-black color, indium oxide is very expensive, gallium and its compounds are highly toxic

[0003] Therefore, the application of the above-mentioned conductive powder is greatly limited, and aluminum-doped zinc oxide (ZAO) has many advantages such as wide source of raw materials, low cost, light color, non-toxicity, and high conductivity second only to ITO. And it is more and more favored by people, and will play an increasingly important role in the fields of electromagnetic wave shielding materials and anti-static coating materials.

[0004] Doped zinc oxide nano conductive powder material and its preparation method (country: China, publication number: 102723120A, publication date: 2012-10-10), the product has high purity and small particle size, but the preparation method uses hydrothermal Preparation method requires high temperature and high pressure, which is not conducive to the realization of industrialization

[0005] A new process for the preparation of nano-conductive zinc oxide (country: China, public number: 1876570, public date: 2006-12-13), the process prepares conductive zinc oxide by doping elements (gallium, aluminum, indium) Good powder, but the process uses a doping-co-precipitation one-step method, the resulting particle agglomeration phenomenon is serious, the powder doped with elements gallium and indium is toxic, and the calcination process requires a hydrogen atmosphere, which is less safe

[0006] A high-conductivity aluminum-doped zinc oxide nanopowder and its preparation method (country: China, publication number: 101274775, publication date: 2008-10-01), the conductive powder prepared by this method has a small particle size, Good dispersion, but the preparation process requires high temperature and high pressure, and the sintering process requires hydrogen reduction, which is highly dangerous