Optical Properties of Pure and Alloyed Silver-Copper Nanoparticles Embedded and Coupled in Dielectric Matrixes

AbstractIn this study by using the boundary element method, influence of various parameters on the response to electromagnetic radiation for pure and alloyed silver-copper was investigated. The results demonstrate decreasing interparticle gap from 20nm to 1nm for silver coupled nanoparticles leads to shifting the wavelength of optical extinction peak from 362nm to 393nm. Decreasing interparticle gap from 20nm to 1nm for Cu coupled nanoparticles leads to shifting the wavelength of optical extinction peak from 323nm to 336nm. By an increase in the medium refractive index of 1 to 2 the peak of optical extinction for a coupled Cu nanoparticles with 1nm gap distance the wavelength of plasmon resonance peak shifted from 336nm to 366nm and longitudinal plasmon resonance peak shifted from 498nm to 559nm. By changing the composition of an alloy of copper and silver nanoparticles with diameter of 10nm in dielectric matrix with refractive index 1.3 the wavelength of plasmon resonance peak shifted from 378nm for pure silver nanoparticles to 530nm for pure copper nanoparticles. In addition for Cu-Ag alloy coupled nanoparticles with 1nm interparticle gap, the wavelength of resonance peak shifted from 420nm for pure silver nanoparticles to 544nm for pure copper nanoparticles. In the case of embedded nanoparticles for coupled silver nanoparticles with 6nm gap distance, the wavelength of resonance peak shifted from 396nm to 409nm, and for coupled silver nanoparticles with 2nm gap distance, the wavelength of resonance peak shifted from 414nm to 430nm. Furthermore for coupled Cu nanoparticles with 2nm gap distance, the wavelength of resonance peak shifted from 575nm to 582nm. The results could be employed for plasmatic sensor design and fabrication

Characterization of Al-CNT Composite Nanoparticles Synthesized by Electrical Explosion of Wire in Acetone

In this study, electrical wire explosion has been used to produce aluminum carbon nanotube (Al-CNT) nanocomposite particles in acetone medium. In order to synthesize Al-CNT nanocomposites, initially, CNTs were ultrasonically dispersed. Then, aluminum wire was exploded in this medium. Synthesized samples were characterized by Fourier Transform Infrared (FTIR) spectroscopy and Transmission Electron Microscopy (TEM) methods. The results exhibited formation of spherical nanoparticles in the medium. The average diameter of nanoparticles was 4 nm. Moreover, attained nanoparticles remained stable in acetone. Results revealed a good interaction between aluminum nanoparticles and CNTs in this medium. It is concluded that acetone is a suitable medium for synthesizing Al-CNT nanocomposite as appropriate dispersion of Al-CNT nanoparticles can be achieved in this medium