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Abstract Ce/Ti mixed metal oxide thin films have well known optoelectrical properties amongst several other physio-chemical properties. Changes in the structural and mechanical properties of magnetron sputtered Ce/Ti oxide thin films on Si (100) wafers with different Ce:Ti ratios are investigated experimentally and by modelling. X-ray Photoemission Spectroscopy (XPS) and X-ray diffraction (XRD) confirm the primary phases as trigonal Ce 2 O 3 and rutile form of TiO 2 with SiO 2 present in all prepared materials. FESEM imaging delivers information based on the variation of grain size, the mixed Ce/Ti oxides providing much smaller grain sizes in the thin film/substrate composite. Nanoindentation analysis concludes that the pure cerium oxide film has the highest hardness value (20.1 GPa), while the addition of excess titanium oxide decreases the hardness of the film coatings. High temperature in-situ XRD (up to 1000 °C) results indicate high thermal phase stability for all materials studied. The film with Ce:Ti = 68%:32% has a new additional minor oxide phase above 800 °C. Contact angle experiments suggest that the chemical composition of the surface is insignificant affecting the water contact angle. Results show a narrow band of 87.7–95.7° contact angle. The finite element modelling (FEM) modelling of Ce/Ti thin film coatings based on Si(100); Si(110); silica and steel substrates shows a variation in stress concentration. [ABSTRACT FROM AUTHOR]

CrN, CrTiN and CrAlN coatings were deposited on Si (100) via co-sputtering chromium, titanium and aluminum targets by using unbalanced magnetron sputtering, respectively. And the relevant microstructure and composition were characterized. The influences of the doping elements on the microstructural and electrochemical properties of CrN coatings in the artificial seawater were analyzed via the open circuit potential (OCP), electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization tests. As a result, the CrN coating exhibits the favorable corrosion resistance. On the contrary, the easy occurrence of hydration reaction for AlN would lower the compactness of CrAlN, subsequently deteriorate its corrosion resistance. Thus, the CrAlN coating presents the worst electrochemical properties in spite of its highest electrical resistivity. In particular, the CrTiN coating exhibits the outstanding corrosion resistance with relatively higher charge transfer resistance (R ct ), polarization resistance (R P ) due to its great compactness. [ABSTRACT FROM AUTHOR]

Chromium nitride (CrN)-based materials display broad applications as protective coatings for automotive, power generation and aerospace industries, in which surfaces are often subjected to wear and corrosion. By using an appropriate choice of dopant, one can further increase the mechanical hardness, corrosion and oxidation resistance of these coatings. In order to identify the effect of dopants on the structural evolution and surface electronic properties of CrN coatings, Cr 1- z (Al/Si) z N coatings were prepared by magnetron sputtering and then characterized via X-ray diffraction (XRD) and soft X-ray synchrotron radiation Near-edge X-ray Absorption Fine Structure (NEXAFS) studies around N K -edge. Higher degree of crystallinity of the coatings were identified through XRD studies. The bonding structure, of the doped CrN coating, was analyzed by Near-edge X-ray Absorption Fine Structure (NEXAFS) measurements performed around the N K -edge (390–450 eV) in the Auger electron yield (AEY) and total fluorescence yield (TFY) modes. NEXAFS analysis revealed Cr 3d (Al3 p /Si3 p )N2 p hybridizations in Cr 1- z (Al/Si) z N compositions and complex structure splitting via spin–orbit interaction of the Cr3 d levels. [ABSTRACT FROM AUTHOR]