Facial synthesis of Cu@Ag core-shell particles through temperature gradient method with excellent oxidation resistance

To improve the oxidation resistance of Cu particles, the temperature gradient method is used to prepare Cu@Ag core-shell particles (TG-Cu@AgCSPs) with uniform particle size and enhanced oxidation resistance. The TG-Cu@AgCSPs are spherical, with an average size of 2.9 μ m, and the average thickness of the Ag shells is 280 nm. The morphological analysis and thermogravimetric results show that the TG-Cu@AgCSPs possess denser Ag shells and better oxidation resistance compared to core-shell particles prepared by the thermostatic method. The thermal oxidation behavior of TG-Cu@AgCSPs is investigated by heating in air. When heated below 300°C, the Ag shells can keep intact morphology and protect the Cu cores from oxidation. Whereas the original Cu particles will be oxidized at 150°C. In addition, the TG-Cu@AgCSPs are prepared as low-temperature conductive pastes to investigate their electrical properties. Compared with commercial Cu@Ag core-shell particles, the TG-Cu@AgCSPs possess more outstanding performance advantages and have the potential for commercial applications.