With the development of microelectronics products with high density and high power, it is urgent to improve the electrical and thermal conductivity of electronic paste to achieve the new requirements of packaging materials. In this work, a new synthesis method of Ag-MWCNTs was designed: Firstly, carboxylated MWCNTs and stannous chloride were used as raw materials to prepare high-loading-rate Sn-MWCNT composite material to ensure the high loading rate of metal on the MWCNT surface. Then, Ag-MWCNT composite material was prepared by the chemical displacement method to solve the problem of the low loading rate of silver nanoparticles on the MWCNT surface. On the basis of this innovation, we analyzed and compared the electrical, thermal, and mechanical properties of Ag-MWCNT composite electronic paste. Compared with the electronic paste without adding Ag-MWCNTs, the resistivity was reduced by 77%, the thermal conductivity was increased by 66%, and the shear strength was increased by 15%. Therefore, the addition of Ag-MWCNTs effectively improves the electrical, thermal, and mechanical properties of the paste, making it a promising and competitive choice for new packaging materials in the future.

This study focused on the flexible Ag/AgCl biomedical electrode fabricated by screen printing. It systematically investigated the influence of the Ag/AgCl paste on its performance. By adjusting the type of silver powder and the mass ratio of Ag to AgCl, multiple groups of Ag/AgCl pastes were prepared, and their conductivity, microstructure, electrochemical properties, and mechanical stability were systematically characterized. The research results indicated that the specific surface area of the silver powder and the ratio of Ag to AgCl significantly affected the resistivity of the paste and the interface structure of the electrode. When using high specific surface area sheet-like silver powder H and an Ag:AgCl ratio of 5:5, the prepared electrode exhibited the best comprehensive performance: a lower resistivity (2.16 × 10⁻⁷ Ω·m), stable open-circuit voltage, good redox reversibility, and an impedance lower than that of commercial electrocardiogram electrodes. Further verification through an electrocardiogram detection system confirmed that this electrode could clearly and stably collect human electrocardiogram signals, meeting the practical requirements of electrocardiogram detection. This study provided an important theoretical and experimental basis for the development of high-performance and low-cost screen-printed Ag/AgCl flexible electrodes.