High-conductive ultra-thin metallic wires, as basic structures in electronic devices, are highly demanded but challenging to improve the integration level and miniaturization of the devices. In this study, an efficient laser direct writing approach was proposed and aimed at preparing Ag wires with widths as narrow as 2 μm by irradiating the AgNO3-polymer film with a compact blue-violet laser. A comprehensive exploration of various parameters was conducted, leading to the optimization of Ag wires exhibiting an impressively low resistivity of 2.35×10-7Ω·m. In addition, an Ag wire prepared by laser direct writing on the flexible PEN substrate shows high tolerance to the inward and outward bending, demonstrating excellent flexibility and mechanical stability. On this basis, a UV-light detector based on the laser-irradiated interdigitated Ag patterns and sensitive CdS nanorods was demonstrated with high sensitivity and fast response.
The content of chloroacetic acid in water is mandatory, so rapid and accurate detection is of great significance for environmental health. Silver has a strong specific interaction with chloridion and its three-dimensional interconnected ligaments are proved to have higher activity. Herein, a self-supported nanoporous skeleton was constructed on the surface of silver wire by directly electrochemical alloying in ZnCl2–glycol solution at 140 °C and subsequently dealloying in sulfuric acid solution. AgZn and AgZn3 alloys are formed by electrodeposition process, and the nanoporous skeleton of elemental silver is formed after dealloying. The interconnected ligaments are uniform and the pore size is about 10–200 nm. The cyclic voltammetry showed that the self-supported nanoporous skeleton of the silver wire electrode exhibited high electrocatalytic activity for trichloroacetic acid. Detected by chronoamperometry, the results show that the detection limit is 70 nM (S/N = 3) in the concentration range of 0.14–549 μM, and the sensor has high sensitivity, good reproducibility and anti-interference. And by detecting the recovery rate of trichloroacetic acid in the tap water, river water and industrial wastewater, the sensor proves the practicality of the prepared electrode.
Yushan Li,Ningjing Zhou,Xin He,Shuai Zhang,Dezhi Zhu,Zhijun Ma
Porous metal wires are promising in various applications, such as catalysis, energy storage and conversion, electrochemical sensing, and so forth. However, controllable fabrication and structural tuning of porous metal wires remains a daunting challenge. Here, we report the fabrication of 3D porous silver wires based on a template-assisted electroless deposition (ELD) method using an electrospinning-derived elastomer yarn as the template. After the calcination, the elastomer yarn with the deposition of silver nanoparticles can be converted into a 3D porous metallic silver wire with a conductivity higher than 3600 S/cm and a porosity of 86%. The porous structure of the wire could be tuned by changing the repeating cycles of the ELD process for loading silver nanoparticles. More importantly, the electrospinning-based fabrication strategy enables us to incorporate an insulating fibrous layer on the silver wire to impart advanced functionalities. As a proof of concept, a porous silver wire containing a concentric layer of SiO2 microfibers was prepared, and its application as a wire-shaped capacitor for liquid sensing was demonstrated. Benefitting from its completely inorganic nature, high porosity, and chemical stability, the composite wire could sense various organic solvents as well as aqueous solutions with high sensitivity, reliability, and long-term-use stability.