Ultrasonic Influence on Plasmonic Effects Exhibited by Photoactive Bimetallic Au-Pt Nanoparticles Suspended in Ethanol

Abstract

The optical behavior exhibited by bimetallic nanoparticles was analyzed by the influence of ultrasonic and nonlinear optical waves in propagation through the samples contained in an ethanol suspension. The Au-Pt nanoparticles were prepared by a sol-gel method. Optical characterization recorded by UV-vis spectrophotometer shows two absorption peaks correlated to the synergistic effects of the bimetallic alloy. The structure and nanocrystalline nature of the samples were confirmed by Scanning Transmission Electron Microscopy with X-ray energy dispersive spectroscopy evaluations. The absorption of light associated with Surface Plasmon Resonance phenomena in the samples was modified by the dynamic influence of ultrasonic effects during the propagation of optical signals promoting nonlinear absorption and nonlinear refraction. The third-order nonlinear optical response of the nanoparticles dispersed in the ethanol-based fluid was explored by nanosecond pulses at 532 nm. The propagation of high-frequency sound waves through a nanofluid generates a destabilization in the distribution of the nanoparticles, avoiding possible agglomerations. Besides, the influence of mechanical perturbation, the container plays a major role in the resonance and attenuation effects. Ultrasound interactions together to nonlinear optical phenomena in nanofluids is a promising alternative field for a wide of applications for modulating quantum signals, sensors and acousto-optic devices.

Manufacture of porous carbon thin films for energy storage

“…High surface carbon materials (nanotubes, aerogels, activated carbons) have properties such as water desalination or carbon dioxide (CO2) capture [2]. Carbon can also be used in microscopic measurements as a carbon-coated grid as previously reported [3] [4]. on the other hand, it has been reported that mechano-optical effects occur in nanotubes in ethanol solution [5].…”

Special Issue: Photoactive Materials: Synthesis, Applications and Technology

“…In a second paper regarding the optical properties of nano-particles [ 6 ], Hurtado-Aviles et al studied the influence of an ultrasonic stimulus on the plasmonic resonance of Au–Pt nano-particles in an ethanol suspension. The presence of the ultrasonic waves in the suspension prevented any agglomerations of the nano-particles, and it was found that the light absorption associated with surface plasmon resonance was modified by the presence of the ultrasonic wave.…”