Influence of Fe2O3 on non-isothermal crystallization kinetics and microstructure of lithium titanium phosphate glass-ceramics

The crystallization behavior and microstructure of Li2O-Ti2O-P2O5-Fe2O3 glass-ceramic were investigated by means of differential thermal analysis (DTA), X-ray diffraction (XRD) and scanning electron microscopy (SEM). Crystallization kinetic parameters including the activation energy for crystallization (E-c) and the Avrami exponent (n) were also measured. The activation energy for crystallization was found to be 656 kJ/mol and 295 kJ/mol, respectively, in the Fe2O3-free and 5 weight ratio Fe2O3 containing glasses. The FTIR spectra revealed a strong band due to the influence of Fe2O3 content on different phosphate groups. Impedance spectroscopy studies suggest that the ionic conductivity of the glass-ceramics containing the optimized Fe2O3 content has been improved as compared with the Fe2O3 free one. According to the obtained results. LiTi2(PO4)(3) precipitated as near spherical and pyramid-like crystals. (c) 2014 Elsevier B.V. All rights reserved.