Chapters authored
Structural and Electrochemical Properties of Cementitious and Hybrid Materials Based on Nacrite
This chapter gives possible valorization of a well-crystallized Tunisian nacrite as an interesting clay mineral belonging to the kaolin group: The first part of the chapter aims to produce a new synthetic material labeled ‘‘metanacrite”. Metanacrite is a supplementary cementitious material originated by heating a raw Tunisian nacrite at 823 K. The structure of the amorphous synthetic product was corroborated by X-ray diffraction (XRD) and infrared spectroscopy (IR). The decomposition of the silicate framework was confirmed by transmission electron microscope (TEM). The obtained metanacrite was also examined by electrochemical impedance spectroscopy (EIS). Accordingly, a semiconductor behavior of the novel synthetic material is evidenced. The second part of this chapter deals with the intercalation of lithium chloride salt between the planar layers of this Tunisian nacrite. The intercalation leads to a stable hybrid material that after calcination under inert atmosphere at 723–873 K induces an amorphous hybrid. The structural identification of the obtained nacrite–LiCl hybrid was determined by means of XRD, IR, TGA, and EIS. Finally, the resulting amorphous hybrid shows a superionic behavior with high ionic conductivity up to 10–2 S.m–1, good electrochemical stability, and can be used as an innovative solid electrolyte in lithium batteries and other electrochemical devices.
Part of the book: Clays, Clay Minerals and Ceramic Materials Based on Clay Minerals