Overview of the TiC/TiO2 (rutile) interface

The structural and chemical characterization of the TiC/rutile interface that grows in the high-temperature and low-oxygen partial pressure oxidation of TiC single crystals is reported. Based on previous data of micro-Raman and Auger electron spectroscopy (AES)–scanning electron microscopy (SEM) profiles of the TiC/rutile interface cross-section, a Ti oxycarbide phase is expected to form at the TiC/rutile interface. In order to be consistent with the above mentioned data, Ti oxycarbide should form by partial substitution of C with O without producing any change in the rock-salt structure of TiC except to small changes in the lattice parameter. Following the Ti oxycarbide e-gun synthesis by X-ray diffraction (XRD) analysis, the enhancement of the O substitution in the C sublattice of TiC has been shown. The final product has been identified by chemical analysis as Ti1.00±0.01C0.49±0.01O0.4±0.1 having a XRD spectrum almost identical to TiC with a relative change of the lattice parameter equal to −0.8%. This result confirms the reason why no other signals other than the signals of amorphous carbon and rutile appear in the micro-Raman profiles of the TiC/TiO2 interface as well as the reliability of the oxidation mechanism elsewhere proposed.