Study on surface enhanced Raman scattering of Au and Au@Al2O3 spherical dimers based on 3D finite element method

Abstract

In this paper, the surface enhanced Raman scattering (SERS) characteristics of Au and Au@Al2O3 nanoparticle dimers were calculated and analyzed by using finite element method (3D-FEM). Firstly, the electric field enhancement factors of Au nanoparticles at the dimer gap were optimized from three aspects: the incident angle of the incident light, the radius of nanoparticle and the distance of the dimer. Then, aluminum oxide is wrapped on the Au dimer. What is different from the previous simulation is that Al2O3 shell and Au core are regarded as a whole and the total radius of Au@Al2O3 dimer is controlled to remain unchanged. By comparing the distance of Au nucleus between Au and Au@Al2O3 dimer, it is found that the electric field enhancement factor of Au@Al2O3 dimer is much greater than that of Au dimer with the increase of Al2O3 thickness. The peak of electric field of Au@Al2O3 dimer moves towards the middle of the resonance peak of the two materials, and it is more concentrated than that of the Au dimer. The maximum electric field enhancement factor 583 is reached at the shell thickness of 1 nm. Our results provide a theoretical reference for the design of SERS substrate and the extension of the research scope.

Arrays of Ag-nanoparticles decorated TiO2 nanotubes as reusable three-dimensional surface-enhanced Raman scattering substrates for molecule detection

“…In comparison to traditional technologies such as infrared (IR) spectroscopy and gas chromatography (GC) ( Song et al, 2016 ; Li and Chin, 2021 ), surface-enhanced Raman scattering (SERS) spectroscopy has lower cost and comparable or even more superior sensitivity. Therefore, SERS technology has bright prospects in many fields, such as trace detection, environmental monitoring, food safety, biochemical sensing and so on ( Zhu et al, 2021a ; Li et al, 2021 ; Yan et al, 2021 ). SERS as a powerful technology can detect trace molecules in a fast, sensitive and non-destructive way and provide molecular “fingerprint” information.…”

Methane to Methanol Conversion Using PEM Fuel Cell and PdAu/ATO Nanomaterials

“…For all materials containing gold, it is possible to observe a feature at potentials less negative than -0.4 V, which is assigned to the Au-O stretching vibration of Au oxide and appears at approximately 559 cm -1 [41], and this potential is shift for more negative with gold contend increases. At 635 cm -1 is referent to the Au-O and Au-OOH vibrations [42], and this bands decreases with addiction of Pd. The band observed at 602 cm -1 in SnO2 was overlapping with this band, while distinct bands were observed at 794, 974, and 1166 cm −1 , which can be attributed to Nafion [43].…”

SARS-CoV-2 Virus-like Particles with Plasmonic Au Cores and S1-Spike Protein Coronas

“…For the studies, the solution of VLPs was drop-casted onto a 12 nm-thick Au film deposited onto an α-Al 2 O 3 (0001) (ALO) single-crystal substrate. The selection of the substrate was not incidental, as gold films deposited onto dielectric substrates enhance the SERS effect. , In addition to VLPs and VLP/mAb complexes, measurements were also performed for clean Au/ALO, as well as AuNPs, AuNPs/BSSP, S1 proteins, and mAbs, deposited from solutions onto Au/ALO. In the case of a clean Au/ALO substrate, bands located at 416, 428, 448, 488, 575, 706, 748, 826, 1266, 1370, 1400, and 1657 cm –1 were observed (Table S1).…”