Low-resistivity sintered silver-coated copper paste and preparation method thereof

The invention belongs to the technical field of electronic paste, and particularly relates to low-resistivity sintered silver-coated copper paste and a preparation method thereof. The silver-coated copper paste comprises the following components in percentage by mass: 50%-80% of silver-coated copper powder and 20%-50% of an organic carrier, and the silver-coated copper powder is prepared by coating copper powder with the particle size of 50nm-1 [mu] m with silver. The method specifically comprises the following steps: firstly, preparing a deoxidized copper dispersion solution and a reducing agent solution; further, the deoxidized copper dispersion liquid is added into a reducing agent solution, and copper powder/reducing agent turbid liquid is prepared; furthermore, a silver nitrate solution is prepared, the silver nitrate solution is added into the copper powder/reducing agent turbid liquid for reaction, and the silver-coated copper powder can be obtained after suction filtration and drying are conducted on