Electrochemical rutile and anatase formation on PEO surfaces

SURFACE & COATINGS TECHNOLOGY

卷:315

Article

Friedemann, A. E. R.^1,2,3  Gesing, Th. M.^2,3  Plagemann, P.¹ 

[1] FRAUNHOFER Inst Fertigungstech Angew Mat Forsch I, Wiener Str 12, D-28359 Bremen, Germany

[2] Univ Bremen, Inst Anorgan Chem & Kristallog, Leobener, Str NW2,Bibliothekstr 1, D-28359 Bremen, Germany

[3] Univ Bremen, MAPEX Ctr Mat & Proc, Bibliothekstr 1, D-28359 Bremen, Germany

关键词: Plasma electrolytic oxidation;    Tio(2) layer;    Anatase;    Rutile;    Crystallinity;    Photocatalytic activity;   

DOI  :  10.1016/j.surfcoat.2017.01.042

来源: Elsevier

【 摘 要 】

A highly porous surface with a high crystalline content and resultant photocatalytic activity is ensured through the process of plasma electrolytic oxidation on pure titanium. In the present study the morphology, crystallinity and photocatalytic activity of plasma electrolytic oxidized TiO2-surfaces were investigated. The surfaces were prepared in acidic and alkaline electrolytes over an applied voltage range between 50 V and 300 V to optimize the crystalline and photocatalytic properties. Scanning electron microscopy (SEM) and X-ray powder diffraction (XRD) were selected to determine the morphologies which differ according to the type of electrolyte as well as the crystal structures of anatase and rutile on the surface material, which increase with the applied voltage. The oxide surfaces did not show morphological differences compared to typical PEO surfaces with the exception of oxide films obtained in H2SO4-solution which also exhibited an astounding amount of rutile even with low applied voltages. The increased parts of anatase and rutile on the surfaces resulted in photocatalytic activity, which was investigated under UV-light using methylene blue, while the PEO surfaces showed degradation activity. There is an indication that a high proportion of anatase and small amounts of rutile in the PEO layers positively influence photocatalytic activity.(C) 2017 Elsevier B.V. All rights reserved.

【 授权许可】

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