The preparation of pH-sensitive Pd catalyst ink for selective electroless deposition of copper on a flexible PET substrate

Silver nanoparticle conductive inks: synthesis, characterization, and fabrication of inkjet-printed flexible electrodes

Flexible electronics can be developed with a low-cost and simple fabrication process while being environmentally friendly. Conductive silver inks have been the most applied material in flexible substrates. This study evaluated the performance of different conductive ink formulations using silver nanoparticles by studying the material properties, the inkjet printing process, and application based on electrical impedance spectroscopy using a buffer solution. Silver nanoparticles synthesis was carried out through chemical reduction of silver nitrate; then, seven conductive ink formulations were produced. Properties such as resistivity, viscosity, surface tension, adhesion, inkjet printability of the inks, and electrical impedance of the printed electrodes were investigated. Curing temperature directly influenced the electrical properties of the inks. The resistivity obtained varied from 3.3 × 10⁰ to 5.6 × 10^-06 Ω.cm. Viscosity ranged from 3.7 to 7.4 mPa.s, which is suitable for inkjet printing fabrication. By using a buffer solution as an analyte, the printed electrode pairs presented electrical impedance lower than 200 Ω for all the proposed designs, demonstrating the potential of the formulated inks for utilization in flexible electronic devices for biological sensing applications.

Preparation of Conductive Polyester Fibers Using Continuous Two-Step Plating Silver

Polyester fibers are used in various fields, due to their excellent mechanical and chemical stability. However, the lack of conductivity limits their application potential. In order to prepare conductive polyester fibers, silver is one of the most widely used materials to coat the surface of the fibers. This work aimed to prepare silver-coated polyester fibers by a continuous two-step method, which combined the operations of continuous electroless plating and electroplating. Meanwhile, we designed specialized equipment for the continuous plating of silver on the polyester fibers under a dynamic condition. The mechanical property, washability, electrical resistivity, and electrical conductivity of the resultant conductive polyester fibers obtained from different silver-plating conditions were also characterized. The results demonstrated that the conductive fibers prepared by continuous two-step silver plating equipment, had good electrical conductivity with better mechanical properties and washability.

Chemical formation of soft metal electrodes for flexible and wearable electronics

Efficient chemical approaches to fabricating soft metal electrodes aiming at wearable electronics are summarized and reviewed.