Highly‐Ordered, 3D Petal‐Like Array for Surface‐Enhanced Raman Scattering

Abstract

Despite the great potential of the application of surface-enhanced Raman scattering (SERS), the difficulty in fabricating suitable SERS substrates is still a problem. Based on the self-assembly of silica nanoparticles, a simple method is here proposed to fabricate a highly-ordered, 3D, petal-like arrayed structure (3D PLAS) that serves as a promising SERS substrate for both its high reproducibility and enormous SERS enhancement. Such a novel structure is easily achieved by anisotropically etching a self-assembly bilayer of silica nanoparticles, followed by metal deposition. The SERS performance of the 3D PLAS and its relationship with the main parameters, including the etching time, the diameter of silica nanoparticles, and the deposited metal film, are characterized using 632.8 nm incident light. With Rhodamine 6G as a probe molecule, the spatially averaged SERS enhancement factor is on the order of 5 × 10(7) and the local enhancement factor is much higher, both of which can be improved further by optimizing the parameters.

Three-dimensional SERS hot spots for chemical sensing: Towards developing a practical analyzer

“…Many top-down fabrication strategies have been put forward to build 3D SERS substrates, such as optical lithography, deep reactive ion etching (RIE), [44,45] electron beam lithography (EBL), [45,46] and ion beam milling. While majority of the structures investigated mainly revolves around pillars, cylinders or columnar architectures, [47][48][49] they may not be the most efficient design for SERS.…”

Hierarchical 3D SERS Substrates Fabricated by Integrating Photolithographic Microstructures and Self‐Assembly of Silver Nanoparticles

“…Many fabrication strategies have been put forward to build 3D SERS substrates, such as reactive ion etching, template metal deposition, electron beam lithography and direct chemical growth . While majority of the structures investigated mainly revolves around pillars, cylinders or columnar architectures, they may not be the most efficient design for SERS.…”

High‐Density Hotspots Engineered by Naturally Piled‐Up Subwavelength Structures in Three‐Dimensional Copper Butterfly Wing Scales for Surface‐Enhanced Raman Scattering Detection

“…Recent works have provided excellent SERS substrates based on sub‐micrometer metallic structures, which were mainly created either by forming plasmonic nanoparticles (NPs) with special shapes and core‐shell structures,9–12 or by performing lithographic approaches, to chase high density “hotspots” where electromagnetic (EM) fields are localized 13–16. Compared with two dimensional counterparts, three dimensional (3D) sub‐micrometer structures have the potential to further expand the arrangement of hotspots along the third dimension, which could in turn increase the hotspot density 17–20. However, it is quite difficult to conveniently generate reproducible 3D sub‐micrometer structures with such hotspots at a low cost for research and for commercial applications.…”