アイテム詳細

要旨

The role of the nitrogen incorporation into titanium, its chemical nature, the location in the titanium lattice and its electrochemical performance were investigated by a combination of several spectroscopy and microscopy techniques using samples prepared by CVD of NH₃ at different temperatures and successive electrochemically tested in 1 M of HClO₄. We found that nitrogen is incorporated in either the interstitial or substitutional site of the lattice depending on the preparation temperature modifying strongly its corrosion resistance which was ascribed to the N 2p hybridization with the Ti 3d orbitals. It was found that at low temperature the N 2p orbitals were more likely to hybridize with Ti_3d-t_2g orbitals while higher temperature favors the hybridization with the Ti_3d-e_g orbitals. This is responsible for the corrosion resistance shown by the samples prepared at higher temperature.