Silver nanowires (AgNWs) are important materials to fabricate flexible transparent conductors (FTCs) for next-generation wearable electronics. However, the electrochemical instability still limits their practical applications in electrochemical devices. Herein, highly...

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As an indispensable aspect of flexible and printed electronics, flexible strain sensors composed of silver nanowires (AgNWs) have attracted significant attention recently. However, low resolution and large wire‐wire contact resistance still impede the stability and sensitivity of AgNW‐based flexible strain sensors. Herein, self‐reduced soldered AgNW pattern is fabricated by combining the high‐resolution electrohydrodynamic (EHD) printing and joining of AgNWs. The resolution achieved by EHD printing is up to ≈20 µm. The contact resistance between AgNWs is greatly reduced by depositing Ag atoms at the AgNW junctions while EHD printing Ag ion ink on as‐prepared AgNW pattern. After self‐reduced soldering process, the sheet resistance decreases from 14.8 to 2.13 Ω sq−1. This process can be conducted under room temperature and ambient conditions and requires no external assistance from heat, light, or mechanical pressing. Furthermore, the deposited Ag atoms at the junctions remarkably improve the sensitivity (gauge factor 14.5–37.9) and stability (over 5000 stretching cycles with 25% strain). This superior sensitivity and stability occur because nano‐junctions induced by the self‐reduced soldering process significantly reduce the initial resistance and enable a robust network structure. This EHD‐based technique for nanojoining of AgNWs demonstrates its potential for flexible and wearable electronics.

Due to the harsh working environments up to 600 °C, the exploration of high-temperature interconnection materials is significantly important for high-power devices. In this study, a hybrid paste including Cu@Ag core–shell microparticles (MPs) and Ag nanoparticles (NPs) was designed to achieve Cu–Cu bonding. The Cu@Ag MPs exhibited excellent oxidation stability in an air atmosphere with the Ag layer coating on the Cu core. Ag NPs fill the pores among the Cu@Ag MPs and reduce the sintering temperature of the hybrid paste. The Cu–hybrid paste–Cu joints were formed via electromagnetic induction heating within approximately 15 s. When sintered at 26 kW, the shear strength of the joint reached 48 MPa, the porosity decreased to 0.73%, and the resistivity was down to 13.25 μΩ·cm. Furthermore, a possible interconnection mechanism at the contact interface between the Cu substrate and the sintered hybrid paste was proposed, which is related to the melting point of metal particles and the effect of magnetic eddy currents. This fast bonding technology inspires a new approach to interconnection for high-power devices under high operation temperatures.