Structural Analysis of Brazilian Graphite by X-ray Diffraction, Scanning Electron Microscopy, and Thermogravimetric Analysis with Simultaneous Differential Scanning Calorimetry

The results on X-ray analysis of Brazilian graphite sample are presented. During diffraction pattern indexing and qualitative X-ray phase analysis, it has been found that Brazilian graphite contains three phases of carbon, two of which belong to hexagonal graphite (α-graphite) and one to rhombohedral graphite (β‑graphite), which is confirmed by simultaneous thermal analysis. The unit cell parameters of each phase have been determined and refined. Calculations of conditional phase concentrations in the sample by the least squares method have shown that the conditional concentration of 47-1155 standard (JCPDS database) in the sample is 66%, 1-646 standard is 21.3%, and 2-456 standard is 12.6%. Using scanning electron microscopy, the sample surface topology has been found to be is a flake structure with a large number of particles, the size of which does not exceed 5 μm. The quantitative characteristics of the short-range order have been determined, which have shown that the structure of Brazilian graphite is close to that of hexagonal graphite within the error limits.