Abstract

Subject of study. Nanosized quartz isolated from quartz veins of shungite rocks of Karelia are studied. Aim of study. Quartz nanoparticles from shungite rocks are prepared and examined, and their structural and spectral characteristics are compared with the characteristics of natural quartz from traditional deposits to assess their applications in optics and biomedicine. Method. The samples examined from the quartz veins cutting shungite rocks and reference samples were prepared in the same manner: crushed, washed, dispersed, and centrifuged. Powders and condensates of quartz nanoparticles were analyzed via X-ray diffraction, Raman scattering, and scanning electron microscopy. The size of quartz nanoparticles in aqueous dispersion was estimated from dynamic light scattering data. Main results. According to X-ray diffraction analysis, quartz of shungite rocks can be classified as a low-temperature α-quartz of tetragonal structure (spatial group P41212), and it exhibits a crystallite size of less than 100 nm. The parameters of the crystal lattice and coherent scattering region of the vein α-quartz of shungite rocks were determined after various treatments of the samples under study (dispersion, water treatment, ultrasound). Quartz nanoparticles were isolated and stabilized in aqueous dispersion. The average size of quartz nanoparticles in aqueous dispersion according to dynamic light scattering data was 158.7±89.8nm. This coincided with the particle size in the dispersion condensate films obtained via scanning electron microscopy. Comparison of nanosized quartz of shungite rocks with samples of traditional quartz raw materials via Raman scattering showed that its distinctive feature corresponds to the presence of graphene-like carbon and water phases in the samples. Practical significance. Quartz nanoparticles from shungite rocks, a new unconventional source of quartz raw materials, were obtained and examined in this study. These nanoparticles will find application in nanotechnology materials science for optics, electronics, composite materials production, and biomedicine.

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