SEM investigation of minor constituents of carbide materials prepared from shungite rocks

Abstract

The "SiC-Al 2 OC"-based composite prepared from Karelian shungite rocks has been studied by X-ray diffraction analysis and scanning electron microscopy. SEM investigation has been done to determine the mode and distribution of admixture constituents. It is found that the most common minor phase represents Al-Fe-Si-C-based alloys. Special attention has been given to describing the noble metals admixtures. It is revealed that the noble metals phases occur as separate microsized grains, most of which have been indicated as Au-Ag-Hg amalgam and rarely as Pt-rich compounds. The obtained data can be mainly used to advance technologies for manufacturing carbide-based composite materials from natural carbonaceous rocks. Keywords. Shungite rocks; thermal processing; carbide materials; SiC-Al 2 OC; admixtures; noble metals.

Shungite Carbon as Unexpected Natural Source of Few-Layer Graphene Platelets in a Low Oxidation State

“…A preliminary analysis of the spectrum indicates that the principal bulk crystalline material is quartz, which gives rise to the most intense peaks at about 26 and 21 deg. , Unfortunately, the signals related to quartz cover those of carbon materials, so that graphite or fullerenes phases main signals are barely observable. The peaks visible at 37 and 46 deg can be attributed to silico-alluminates and iron silicide, respectively . Such heterogeneous composition makes clear how the setting up of an efficient purification procedure was a fundamental task in order to obtain a pure graphene-like carbon phase from the natural material.…”

“…The peaks visible at 37 and 46 deg can be attributed to silico-alluminates and iron silicide, respectively. 49 Such heterogeneous composition makes clear how the setting up of an efficient purification procedure was a fundamental task in order to obtain a pure graphene-like carbon phase from the natural material.…”