Preparation method for superfine copper-silver core shell composite powder for medium-high temperature electronic slurry

Abstract

The invention discloses a preparation method for superfine copper-silver core shell composite powder for medium-high temperature electronic slurry. Copper powder is prepared through a liquid phase chemical reduction method; the copper powder is washed through sulfuric acid, deionized water and ethanol, dried in the vacuum environment and then screened to obtain dried copper powder; zinc oxide, nitric acid and phosphoric acid are mixed, deionized water is added, and phosphating liquid is prepared; the dried copper powder is taken and added in the phosphating liquid to be stirred, washed through deionized water and ethanol to be neutral, filtered, and then dried in the vacuum environment, and thus finished copper powder is obtained; the finished copper powder, a dispersant, a reductant and a complexing agent are mixed, deionized water is added, and thus a disperse system solution of suspended copper powder is prepared; silver nitrate and a complexing agent are added to deionized water to prepare a silver nitrate solution; the silver nitrate solution is dropped into the disperse system solution, and thus silver-coated copper powder is obtained; and the silver-coated copper powder is washed through deionized water and ethanol, filtered, then dried in the vacuum environment and screened, and thus the copper-silver core shell composite powder is obtained. According to the copper-silver core shell composite powder obtained through the preparation method, silver on the surface of the copper-silver core shell composite powder is not likely to fall off, oxidation resistance is high, and the conductive property is stable.

Description

technical field [0001] The invention belongs to the technical field of nanomaterial preparation, in particular to a method for preparing ultrafine copper-silver core-shell composite powder for electronic paste Background technique [0002] With the development of the electronics industry, there is an increasing demand for electronic pastes with gold, silver, copper and other metal powders as the main materials. Silver is widely used because of its good electrical conductivity and thermal stability, but silver is a precious metal and is expensive, thus increasing the production cost of electronic paste, and silver resources are becoming increasingly scarce. Therefore, looking for powdered metals that can replace silver has increasingly become the focus of researchers at home and abroad. Copper has good electrical conductivity and can meet the needs of electronic paste, but copper powder is easily oxidized and forms Cu on its surface. 2 The film of O and CuO seriously affect...

AI Technical Summary

Problems solved by technology

The above methods are to directly plate silver on the surface of copper powder to prepare silver-coated copper powder, but the silver on the surface is easy to fall off, causing the copper powder to leak and be oxidized again, thus affecting the performance of silver-coated copper powder

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