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Abstract Silver nanowires (AgNWs) hold great promise for applications in wearable electronics, flexible solar cells, chemical and biological sensors, photonic/plasmonic circuits, and scanning probe microscopy (SPM) due to their unique plasmonic, mechanical, and electronic properties. However, the lifetime, reliability, and operating conditions of AgNW-based devices are significantly restricted by their poor chemical stability, limiting their commercial potentials. Therefore, it is crucial to create a reliable oxidation barrier on AgNWs that provides long-term chemical stability to various optical, electrical, and mechanical devices while maintaining their high performance. Here we report a room-temperature solution-phase approach to grow an ultra-thin, epitaxial gold coating on AgNWs to effectively shield the Ag surface from environmental oxidation. The Ag@Au core-shell nanowires (Ag@Au NWs) remain stable in air for over six months, under elevated temperature and humidity (80 °C and 100% humidity) for twelve weeks, in physiological buffer solutions for three weeks, and can survive overnight treatment of an oxidative solution (2% H 2 O 2 ). The Ag@Au core-shell NWs demonstrated comparable performance as pristine AgNWs in various electronic, optical, and mechanical devices, such as transparent mesh electrodes, surface-enhanced Raman spectroscopy (SERS) substrates, plasmonic waveguides, plasmonic nanofocusing probes, and high-aspect-ratio, high-resolution atomic force microscopy (AFM) probes. These Au@Ag core-shell NWs offer a universal solution towards chemically-stable AgNW-based devices without compromising material property or device performance.
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This content will become publicly available on July 16, 2025
Decoding the Effect of Synthesis Factors on Morphology of Nanomaterials: A Case Study to Identify and Optimize Experimental Conditions for Silver Nanowires
Silver nanowires (AgNWs) are one kind of nanomaterials for various applications such as solar panel cells and biosensors. However, the morphology of AgNWs, particularly their length and diameter, plays a critical role in determining the efficiency of energy storage systems and the transmittance of biosensors. Thus, it is imperative to study synthesis strategy for morphology control. This study focuses on synthesizing AgNWs through the solvothermal approach and aims to understand the individual and combined effects of three nucleants, NaCl, Fe(NO3)3 and NaBr, on the morphology of AgNWs. Using a modified successive multistep growth (SMG) approach and fine-tuning the nucleant concentrations, this study synthesized AgNWs with controllable aspect ratios, while minimizing the presence of undesirable byproducts like nanoparticles. Our results demonstrated the successful synthesis of AgNWs with favorable morphologies, including lengths of approximately 180 µm and diameters of 40 nm, thus resulting in aspect ratios of 4500. In addition, to assess the quality of the synthesized AgNWs, this work developed computational tools that uses MATLAB to automate the analysis of scanning electron microscope (SEM) images for detecting silver nanoparticles. This automated approach provides a quantitative analysis tool for material characterization and holds the promise for long-term evaluation of diverse AgNW samples, thereby paving the way for advancements in their synthesis and application. Overall, this study demonstrates the significance of morphology control in AgNW synthesis and presents a robust framework for material characterization and quality analysis.
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- Award ID(s):
- 2426614
- PAR ID:
- 10527460
- Publisher / Repository:
- MDPI, Processes
- Date Published:
- Journal Name:
- Processes
- Volume:
- 12
- Issue:
- 7
- ISSN:
- 2227-9717
- Page Range / eLocation ID:
- 1487
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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