Conductive polymer composites (CPCs) containing nanoscale conductive fillers have been widely studied for their potential use in various applications. In this paper, polypyrrole (PPy)/polydopamine (PDA)/silver nanowire (AgNW) composites with high electromagnetic interference (EMI) shielding performance, good adhesion ability and light weight are successfully fabricated via a simple in situ polymerization method followed by a mixture process. Benefiting from the intrinsic adhesion properties of PDA, the adhesion ability and mechanical properties of the PPy/PDA/AgNW composites are significantly improved. The incorporation of AgNWs endows the functionalized PPy with tunable electrical conductivity and enhanced EMI shielding effectiveness (SE). By adjusting the AgNW loading degree in the PPy/PDA/AgNW composites from 0 to 50 wt%, the electrical conductivity of the composites greatly increases from 0.01 to 1206.72 S cm, and the EMI SE of the composites changes from 6.5 to 48.4 dB accordingly (8.0-12.0 GHz, X-band). Moreover, due to the extremely low density of PPy, the PPy/PDA/AgNW (20 wt%) composites show a superior light weight of 0.28 g cm. In general, it can be concluded that the PPy/PDA/AgNW composites with tunable electrical conductivity, good adhesion properties and light weight can be used as excellent EMI shielding materials.

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Alumina nanowire (ANW) films were prepared by etching porous anodic aluminium oxide (AAO), and then humidity sensors with coplanar interdigitated electrodes based on ANWs were fabricated. The ANWs not only present tremendous surface area for water molecule adsorption but also provide efficient sites for attracting water molecules at low relative humidity (RH) levels. The sensors based on the particular morphology of ANWs with large open voids show high sensitivity and small hysteresis, and have fast response and recovery time to humidity. The capacitance rises slowly at a lower RH and increases rapidly after 70% RH, which is associated with the humidity mechanism of chemisorption at lower RH and physisorption at higher RH levels. The impendence analysis suggests that the ANWs are the main factor for sensing humidity, and AAO also contributes to humidity sensing. This study demonstrates that ANWs have promising applications in humidity monitoring.

A particle-free silver precursor ink inkjet-printed as an activator for electroless plating was developed to fabricate highly conductive patterns.