Superplastic Nanomolding of Highly Ordered Metallic Sub‐Micrometer Pillars Arrays for Surface Enhanced Raman Scattering

Abstract

Ordered metallic nanostructures, due to their superior electronic and photonic properties, have played a vital role in wide range of applications, such as metamaterials, plasmonic sensing, electrocatalysis, and energy devices. However, traditional fabrication strategies based on bottom‐up self‐assembly and top‐down lithography are either poor in uniformity or time‐consuming with low scalability. Here, a robust and cost‐effective approach for the fabrication of highly ordered metallic pillars arrays in centimeter scale is presented. This is realized by superplastic nanomolding of metals with highly ordered anodic aluminum oxide templates which are fabricated by the prepatterning of aluminum sheets with bulk metallic glass (BMG) mold, followed by anodizing. The nanopatterning process is rationalized with finite element simulation to avoid the damage of BMG mold. Finally, it is shown that the molded metallic sub‐micrometer pillars arrays can be used for the surface‐enhanced Raman scattering (SERS) with enhancement factor of ≈106. It is found that the SERS performance is influenced by the specific surface area of the pillars in addition to the near‐field intensity. This simple and cost‐effective method not only opens new opportunities for rapid prototyping of large‐scale ordered metallic nanostructures for various applications but also provides guidance for the quantitative analysis on sub‐micrometer scale.

Polariton lasing in Mie-resonant perovskite nanocavity

“…Moreover, the developed method for colloidal synthesis of nanocuboid particles allows for the simple deposition of nanolasers, which makes it suitable for simple integration with various photonic circuits or conductive substrates, being also promising for electrically driven nanolasers in the visible range. Further progress in the fabrication of polariton nanolasers can be attributed to the implementation of template-assisted synthesis, which allows precise control of spatial position and size 79,80 . Additionally, the transition from noble metals to more affordable materials such as aluminum would be worthwhile.…”

Direct laser induced writing of high precision gold nanosphere SERS patterns

“…Several promising alternative techniques have been introduced recently for producing uniform, large scale high sensitive SERS substrates such as superelastic nanomolding of submicrometer metallic pillar arrays, 41,42 optical nanoprinting of colloidal particles by optical gradient and scattering forces on a large variety of different substrates and the formation of lightinduced solid-state protrusion of gold nanowires 43 or the integration of robust SERS substrates by direct induced laser writing (DIW) with femtosecond laser pulses. [44][45][46] In the present work, we report a new time-saving and costeffective method for the fabrication of SERS substrates, that makes use of the local surface plasmon resonance (LSPR) of gold nanospheres (Au-NS) with an average size of about 20 nm.…”

Superplastic Nanomolding of Aluminum Waveguides for Subwavelength Light Routing, Splitting, and Encryption

“…Here we fabricate Al NWs with low cost and high throughput by a superplastic nanomolding (SPNM) technique (Figure a), − where the solid-state diffusion mechanism allows for preparing single-crystalline NWs. , These Al NWs can potentially serve as an excellent optical waveguide with broad spectrum range and long-term stability . We further make functional Al nanophotonic devices of Y-shaped Al NWs via SPNM, which show selective optical routing of chiral light.…”