Abstract
In this study, the hybrid Au–Ag hexagonal lattice of triangular and square lattice of quadrate periodic nanoparticle arrays (PNAs) were designed to investigate their extinction spectra of the localized surface plasmon resonances (LSPRs). First, their simulating extinction spectra were calculated by discrete dipole approximation (DDA) numerical method by changing the media refractive index. Simulation results showed that as the media refractive index was changed from 1.0 to 1.2, the maximum peak intensity of LSPRs spectra had no apparent change and the wavelength to reveal the maximum peak intensity of LSPRs spectra was shifted lower value. Polystyrene (PS) nanospheres with two differently arranged structures were used as the templates to deposit the hybrid Au–Ag hexagonal lattice of triangular and square lattice of quadrate periodic PNAs by evaporation method. The hybrid Au–Ag hexagonal lattice of triangular and square lattice of quadrate PNAs were grown on single crystal silicon (c-Si) substrates, and their measured extinction spectra were compared with the calculated results. Finally, the fabricated hexagonal lattices of triangular PNAs were investigated as a sensor of polychlorinated biphenyl solution (PCB-77) by observing the wavelength to reveal the maximum extinction efficiency (λmax). We show that the adhesion of β-cyclodextrins (SH-β-CD) on the hybrid Au–Ag hexagonal lattice of triangular PNAs could be used to increase the variation of λmax. We also demonstrate that the adhesion of SH-β-CD increases the sensitivity and detection effect of PCB-77 in hexagonal lattice of triangular PNAs.
Highlights
Surface plasmons are coherent delocalized electron oscillations that exist at the interface between any two materials where the real part of the dielectric function changes sign across the interface.If a metal film has two parallel boundaries, the surface plasmon waves will reflect, and the surface plasmons form the particular frequencies of standing waves on the metal nanoparticles with sizes smaller than the wavelength of light
Nanosphere lithography (NSL) was used as the method to fabricate hybrid Au–Ag nanoparticle arrays for the generation of the localized surface plasmon resonances (LSPRs) and investigate their extinction spectra
We investigate periodic nanoparticle arrays as a new and high resolution sensor of polychlorinated biphenyl solution that can measure the variation of λmax in the LSPRs spectra to find the concentration of PCB-77. β-CDs, whose dimension are 7 Å in width and 9 Å in depth, are a series of cyclic oligosaccharides with a hydrophilic exterior and a hydrophobic cavity and they are capable of binding the hydrophobic structures [27,28]
Summary
Surface plasmons are coherent delocalized electron oscillations that exist at the interface between any two materials where the real part of the dielectric function changes sign across the interface. NSL was used as the method to fabricate hybrid Au–Ag nanoparticle arrays for the generation of the localized surface plasmon resonances (LSPRs) and investigate their extinction spectra. Β-CDs can be used as receptors to capture PCBs molecules in solution, which is approved by theoretical simulation [28,29] For this reason, we exploit the binding properties of β-cyclodextrins (β-CDs) for special small organic molecules of PCBs. The localized surface plasmon resonances (LSPRs) can be used as a sensor by observing the variation of wavelength for the maximum extinction efficiency (λmax ) of LSPRs spectra. The fabricated hexagonal lattices of triangular PNAs were dipped in the SH-β-CD solution to find the variation of λmax
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
