This study demonstrates an electrochemical method for the deposition of Ag nanoparticles with anisotropic quasi‐flat structures on solid substrates to form thin films with tunable plasmonic bands covering the full visible range (from 450 to 780 nm). By manipulating the electrodeposition conditions (such as the concentration of capping ligands and pulse voltage), the size and aspect ratio of the deposited silver nanostructures can be controlled and subsequently their plasmonic bands can be tuned. Unlike the free colloidal nanoparticles that often aggregate when exposed to poor solvents, the electrodeposited Ag nanostructured films adhere strongly to the substrates, allowing for their convenient use as effective sensors for the rapid detection of various solvents and their mixtures based on refractive indices. This work provides a new and robust pathway for the preparation of supported plasmonic nanostructured films with controllable morphology and desirable optical property and stability.
Nanostructured silver stands out among other plasmonic materials because its optical losses are the lowest of all metals. However, nanostructured silver rapidly degrades under ambient conditions, preventing its direct use in most plasmonic applications. Here, a facile and robust method for the preparation of highly stable nanostructured silver morphologies is introduced. 3D nanostructured gyroid networks are fabricated through electrodeposition into voided, self‐assembled triblock terpolymer scaffolds. Exposure to an argon plasma degraded the polymer and stabilized the silver nanostructure for many weeks, even in high humidity and under high‐dose UV irradiation. This stabilization protocol enables the robust manufacture of low‐loss silver nanostructures for a wide range of plasmonic applications.
more » « less- Award ID(s):
- 1707836
- PAR ID:
- 10455078
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials Interfaces
- Volume:
- 7
- Issue:
- 23
- ISSN:
- 2196-7350
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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