Gradient plasmonic nanostructures are produced by a straightforward and powerful fabrication strategy—deposition on curved nanomask (DCNM), a physical vapor deposition on a curved mask substrate covered with a monolayer of close‐packed nanospheres. The feasibility of the DCNM strategy is demonstrated by producing well‐ordered Ag gradient single/double nanotriangle (NT) arrays with continuously adjustable color, extinction, localized surface plasmon resonance wavelength, and surface enhanced Raman scattering (SERS). The plasmonic property and the structure gradient are controlled by the size of the mask and the curvature of the curved substrate, as well as the deposition configuration. A plasmonic library of the single/double NT arrays is easily established in a single fabrication. The DCNM strategy can in principle produce a wide range of gradient nanostructures and further be used for flexible components in optical devices, tunable plasmonic SERS sensors, as well as high‐throughput screening of nanostructures.
The dynamic optical switch of plasmonic nanostructures is highly desirable due to its promising applications in many smart optical devices. To address the challenges in the reversibility and transmittance contrast of the plasmonic electrochromic devices, here, a strategy is reported to fabricate color switchable electrochromic films through electro‐responsive dissolution and deposition of Ag on predefined hollow shells of Au/Ag alloy. Using the hollow Au/Ag alloy nanostructures as stable seeds for site‐specific deposition of Ag, elimination of the random self‐nucleation events is enabled and optimal reversibility in color switching is allowed. The hollow structure further enables excellent transmittance contrast between the bleached and colored states. With its additional advantages such as the convenience for preparation, high sensitivity, and field‐tunable optical property, it is believed that this new electrochromic film represents a unique platform for designing novel smart optical devices.
more » « less- Award ID(s):
- 1808788
- NSF-PAR ID:
- 10462869
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Small
- Volume:
- 15
- Issue:
- 7
- ISSN:
- 1613-6810
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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