화학공학소재연구정보센터
Journal of Vacuum Science & Technology A, Vol.24, No.4, 1179-1184, 2006
Thin oxide-free phosphate films of composition formed on the surface of vanadium metal and characterized by x-ray photoelectron spectroscopy
This article reports the preparation of thin (less than 100 angstrom) oxide-free phosphate films of various compositions on vanadium metal. These films are interesting because of their potential for corrosion inhibition, adhesion promotion, and biocompatibility. Valence and core-level x-ray photoelectron spectroscopy (XPS) were used to characterize the films. The valence band spectra obtained were compared with spectra generated from band structure calculations for various vanadium phosphates and from previously reported spectra of vanadium phosphates. Vanadium phosphate coatings were created by the reaction of vanadium metal and different phosphorus-oxygen containing acids: H3PO4, H3PO3, H3PO2, and H2P2O7. This article focuses upon the valence band region which shows significant differences between the four vanadium phosphate films formed as well as clear differences between the these phosphates and vanadium oxides. The valence band spectra are effectively interpreted by band structure calculations. (c) 2006 American Vacuum Society.