Chemical Structure Evolution of Thermally Altered Coal during the Preparation of Coal-Based Graphene and Division of Thermally Altered Zone: Based on FTIR and Raman.

A suite of coal samples near a diabase dike was collected to investigate the structural and functional group evolution of a series of carbon materials prepared from thermally altered coals, explore the influence of thermal metamorphism distance on the structure of coal and its carbon material products, and divide the thermally altered zones. Using Fourier transform infrared and Raman studies, it was found that after demineralization, the aromatic parameters and of the coal structure slightly increase, while the aliphatic parameters CH/CH and oxidation parameter slightly decrease, and the degree of order of the coal structure increases. Graphitization can greatly improve aromatic parameters, eliminate aliphatic structures, and enhance orderliness.

Study on the microstructure of the symbiosis of coal-based graphene and coal-based graphene quantum dots: preparation and characterization.

Coal-based graphene sheets (GS) and coal-based graphene quantum dots (GQDs) are usually prepared separately. In this paper, symbiosis of coal-based GS and coal-based GQDs was successfully prepared with our proposed preparation method by using three raw coals with different reflectance (collected from Qinshui coalfield, Shanxi Province) as carbon sources. The results showed that coal-based GS and coal-based GQDs can exist stably in the symbiosis and are distributed in different layers, and the GQDs are freely distributed between layers of GS.