Light-Trapping SERS Substrate with Regular Bioinspired Arrays for Detecting Trace Dyes

Abstract

Recently, few studies have focused on the light-trapping surface-enhanced Raman scattering (SERS) substrate combined with Si micropyramids and Ag (or Au). However, the Si micropyramids possess no ordered period, which not only affects the repeatability of the SERS signal but also affects the theoretical exploration. Here, the ordered micropyramids with strong light-trapping capability were fabricated by utilizing unconventional nanosphere lithography and anisotropy wet etching technique. Then, the Ag nanobowls were assembled on the ordered micropyramids to form the SERS substrate with bioinspired compound-eyes structure by utilizing the liquid–solid interface self-assembly and transfer technique. Especially, the evidence for the contribution of antireflective Si micropyramids to Raman enhancement was first presented. For this bioinspired SERS substrate, the lowest concentration of R6G that can be detected is 10–13 M with the level of a single molecule, and the relative standard deviation (RSD) is 3.68%. Meanwhile, the quantitative analysis and qualitative analysis can be realized. Especially, simultaneous trace detection of four common dyes (R6G, CV, MG, and MB) in food can be realized, suggesting that this SERS substrate will have a good application prospect in the field of optical sensors.

Smart design of high‐performance surface‐enhanced Raman scattering substrates

“…(D) Ag nanobowls assembled on the ordered micropyramids. Reproduced with permission: Copyright 2021 American Chemical Society 46 . (E) Schematic illustration of evaporating a droplet of citrate‐Ag sols on a fluorosilylated silicon wafer.…”

“… 45 Bioinspired array consists of regular Si micropyramids and regular Ag nanobowls is designed to provide ordered light trapping SERS substrate (Figure 3D). 46 …”

A Simple Polypyrrole/Polyvinylidene Fluoride Membrane with Hydrophobic and Self-Floating Ability for Solar Water Evaporation

“…As shown in Figure 5 c,d, the light-absorption efficiency of the PPy/PVDF(P) membrane with a micropyramid structure is higher than that of the PPy/PVDF membrane without a micropyramid structure. This is because the micro-pyramids of PPy/PVDF(P) can slow down the change of refractive index fromthe air to the membrane surface, thus effectively reducing the reflectivity, which conforms to the effective medium theory (EMT) [ 42 , 43 ]. Meanwhile, as PVDF is an intrinsically hydrophobic material, the contact angle of PPy/PVDF(P) reaches 114°, realizing its self-floating on the water surface, as shown in Figure 5 e,f.…”

The Design and Optimization of an Anti-Reflection Coating and an Intermediate Reflective Layer to Enhance Tandem Solar Cell Photons Capture

“…The power dissipation by reflection remains the best method and the structures of triangular, rectangular, and circular ARC are costly in manufacturing. Furthermore, alternative morphologies, such as the 3D bionic Si photocathode with TiO 2 /MoS 2 , reduce the electrode's reflectivity to 3% and considerably boost its light adsorption capacity [33][34][35]. Additionally, employing self-assembled polymer sphere monolayers as etching masks creates antireflective Si nanopillar arrays.…”