Far-infrared spectra of mesoporous ZnS nanoparticles

• ZnS nanoparticles were synthesized mechanochemically by high-energy milling.
• Specific surface area and texture were examined using BET method.
• Optical properties were investigated by Far-infrared spectroscopy.
• Combined plasmon-LO phonon modes with high phonon damping are observed.
• Increase milling time increases filling factor and decreases cumulative pore volume.

ZnS nanoparticles were synthesized mechanochemically by high-energy milling, with three different milling times (5 min, 10 min and 20 min). Nitrogen adsorption method was used for examining specific surface area and texture of obtained powders. It was found that all samples are completely mesoporous. The optical properties were studied by far-infrared spectroscopy at room temperature in spectral region of 50–600 cm−1. The analysis of the far-infrared reflectivity spectra was made by the fitting procedure. The dielectric function of ZnS nanoparticles is modeled as a mixture of homogenous spherical inclusions in air by the Maxwell-Garnet formula. In the analysis of the far-infrared reflection spectra, appearance of combined plasmon-LO phonon modes (CPPMs) with high phonon damping are observed, which causes decrease of coupled plasmon-phonon frequencies.

Figure optionsDownload high-quality image (128 K)Download as PowerPoint slide