High-dispersity silver powder for preparing front silver paste of solar cell and preparation method of high-dispersity silver powder

Abstract

The invention provides high-dispersity silver powder for preparing front silver paste of a solar cell and a preparation method of the high-dispersity silver powder. The method comprises the steps of preparing a silver salt solution, an organic ligand solution and a reducing agent solution respectively, wherein the reducing agent solution contains ferrous sulfate; adding an acid solution into the silver salt solution, and regulating and controlling the pH value of the silver salt solution to be 5-7; and synchronously dropwise adding the organic ligand solution and the reducing agent solution into the silver salt solution according to the molar ratio of ferrous sulfate to silver salt being (1-2):1, after dropwise adding is completed, carrying out a stirring reaction for preset time, and then carrying out separation, washing and drying to obtain the high-dispersity silver powder for preparing the front silver paste of the solar cell. According to the high-dispersity silver powder for preparing the front silver paste of the solar cell and the preparation method of the high-dispersity silver powder, ferrous sulfate is adopted as a reducing agent, a small amount of organic ligands capable of being chelated with ferrous ions are added in the silver salt reducing process, the silver salt reducing rate can be effectively adjusted by regulating and controlling the adding amount and the adding speed of the organic ligands, the obtained ferrous ion chelate can further wrap the surface of the silver powder, and therefore the high-dispersity silver powder is obtained.

Description

technical field [0001] The invention relates to the technical field of silver powder preparation, in particular to a highly dispersible silver powder for preparing a front silver paste of a solar cell and a preparation method thereof. Background technique [0002] Silver powder has become an important part of electronic paste due to its excellent electrical conductivity, and is currently the most widely used and most used precious metal material in the electronics industry. With the development of miniaturization, integration and intelligentization of electronic products, the market has higher and higher performance requirements for silver powder products. The performance of silver powder with different shapes will be very different under the same use environment. Among them, when flake silver powder is used as a filler to conduct electricity, the silver powder is in surface contact with each other, so the point contact resistance of flake silver powder is much lower than t...

AI Technical Summary

Problems solved by technology

[0007] The above-mentioned methods for preparing flaky nano-silver are not highly controllable, and the prepared flaky silver powder is prone to stacking and agglomeration, and the dispersibility is not good.

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