XRD, FTIR and RAMAN Characterizations of Metakaolin Geopolymers

Nowadays, the production of materials with reduced energy consumption and environmental impact is of considerable interest. In this sense, geopolymers can be considered as important alternatives to Portland cement, as they allow a significant reduction in CO2 emissions and have high mechanical properties and thermal and chemical resistance. In this experimental research, it was decided to prepare geopolymers from metakaolin: this precursor has, in fact, considerable chemical reactivity and allows the production of geopolymers with reduced setting times and with excellent mechanical properties. The characterization of precursors (kaolin and metakaolin) and metakaolin geopolymers was performed using X-ray diffractometry (XRD), Fourier transform infrared spectroscopy (FTIR) and Raman spectroscopy. These techniques have highlighted both the complete transformation by calcination of crystalline kaolin into amorphous metakaolin and the formation of a metakaolin-based geopolymeric paste