Journal of Materials Science, Vol.34, No.9, 2015-2022, 1999
XPS study of titanium species exposed to molten Li2CO3-Na2CO3 in the anodic conditions used in molten carbonate fuel cells
The surface characterization of titanium, titanium oxide and lithium titanate samples exposed to molten Li2CO3-Na2CO3, in the anodic conditions used in molten carbonate fuel cells, was carried out by X-ray Photoelectron Spectroscopy (XPS). Different elements were identified: Ti(IV), O(-II), Li(I) and Na(I). The amounts of adsorbed sodium and lithium carbonates, as well as inserted lithium were estimated by a semi-quantitative XPS analysis in layers of about 50 Angstrom. A broadening of the Ti 2P(3/2) peak was observed. This effect is probably caused by a distorsion of the Li2TiO3 lattice due to the incorporation of lithium within this structure. Li2TiO3 compound was detected by X-ray diffraction (XRD) on Ti, TiO2 as well as Li2TiO3 after treatment in the molten carbonate eutectic.