Microplastic particles in arable soil are expected to impact the environment and potentially human health. The application of municipal biosolids (MBs) to agricultural land presents a further dilemma in that biosolids act as a fertilizer for crop growth, and a disposal pathway for wastewater treatment plants. They are also a direct path for emerging contaminants, such as microplastics to enter the terrestrial environment.
View Article and Find Full Text PDFSpectral lines from the impurities held in stainless steel and in aluminum can be clearly identified in the UV and the visible spectra when emission is laser induced. These spectroscopic lines can be initiated in metal irradiated at moderate laser optical densities of about 2.5×10/.
View Article and Find Full Text PDFSpectrochim Acta A Mol Biomol Spectrosc
November 2022
In order to accurately account for the contribution of different plasmon mediated phenomena when developing materials for applications in photothermal therapy, photovoltaics, or photocatalysis reliable, precise, and localized temperature measurements are required. In this work we applied two surface-enhanced Raman scattering (SERS) spectroscopy based methods to measure the local temperature increase due to the thermoplasmonic effect in gold and silver nanoparticles on thin polystyrene films. The first method relies on the temperature dependence of the anti-Stokes to Stokes Raman bands intensity ratio for a label Rhodamine 6G deposited on the nanostructures.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2020
Plasmonic sensitization of semiconductors is an attractive approach to increase light-induced photocatalytic performance; one method is to use plasmonic nanostructures in core@shell geometry. The occurrence and mechanism of synergetic effects in photocatalysis of such geometries are under intense debate and proposed to occur either through light-induced charge transfer (CT) or through thermal effects. This study focuses on the relation between the dimensions of Ag@CeO nanocubes, the wavelength-dependent efficiency, and the mechanism of light-induced direct CT.
View Article and Find Full Text PDFAn unusually sharp localized surface plasmon resonance (sLSPR) is observed for a monolayer of glass-supported silver nanocubes coated with a thin, 5-20 nm, AlO film. The resonance becomes significantly narrower and stronger while losing optical anisotropy and sensitivity to the surroundings with increasing overlayer thickness. Surface-enhanced Raman scattering excitation profiles indicate an additional enhancement to the electric field brought in by the sLSPR.
View Article and Find Full Text PDFIntegration of nanoparticles into thin films is essential for the development of functional materials, studies of fundamental interfacial processes, and exploitation of inherent properties from the particles themselves. In this work, we systematically investigate the process of incorporation of silver nanocubes into thin polystyrene films at temperatures just above the polymer glass transition. The process of nanocrystal incorporation can be precisely monitored via far-field spectroscopy to observe the response of spatially resolved hybrid plasmon modes.
View Article and Find Full Text PDFPlasmonic properties, such as refractive index sensitivity (RIS), surface enhancement of the Raman signal (SERS), fluorescence quenching, and photocatalytic activity, of monolayers of weakly interacting monodisperse silver nanocubes were qualitatively modified in a very well controlled manner by supporting them on thin silicon films with varying thickness. Such fine tunability is made possible by the strong dependence of the nanocube dipolar (D) and quadrupolar (Q) plasmon mode hybridization on the refractive index of the supporting substrate. By increasing the Si film thickness from zero to ~25 nm we were able to "shift" the D resonance mode by up to 200 nm for ~80 nm cubes without significantly affecting the Q mode.
View Article and Find Full Text PDF