TA2纯钛H3PO4溶液阳极氧化着色膜的表征和电化学分析

Characterization and Electrochemistry Analysis of Colored Films on the Surface of TA2 Pure Titanium by Anodic Oxidation Using Phosphate Acid

摘要:

利用恒压控制阳极氧化法在H3PO4溶液中于TA2纯钛表面制备了不同颜色的氧化膜，利用扫描电镜、X射线能谱仪、X射线衍射仪、X射线光电子能谱仪分析了着色膜的形貌、成分、物相和价态，使用电化学工作站在Hank’s模拟体液中研究了着色膜的Tafel极化曲线和电化学阻抗谱(EIS)。结果表明：SEM显示着色膜由一层表面多孔、内层致密的膜层构成；EMAX显示膜层由单一的Ti和O元素构成；XRD和XPS显示膜层主要由Ti4+和O2-组成，呈非晶态TiO2结构；Tafel极化曲线显示随着电压升高，着色膜腐蚀电位正移、腐蚀电流密度下降；EIS显示随着电压升高，着色膜容抗弧半径增大、阻抗值增加，耐腐蚀性提高

Abstract:

Different colors of oxide films were prepared directly on the TA2 pure titanium by constant voltage anodic oxidation in phosphate acid .The micro-morphologies, composition, components and valence bonds of the colored films were characterized by Scanning electron microscopy (SEM), X-ray diffraction (XRD), Energy disperse spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS). Tafel polarization curves and EIS of the colored films were studied by electrochemical workstation in Hank’s simulated body fluid. The SEM results show that the colored films of pure titanium after anodic oxidation are composed of porous surface and inner dense of oxide. The XRD study shows that the films are possessed of the amorphous structure of titanium dioxide. The XPS results indicate that the films are composed Ti4+ and O2-. With increasing of the voltage, the corrosion potential of colored films increases and corrosion current density decreases according to the Tafel polarization curves. The EIS exhibits that capacitive loop radius are enlarged and impedance values are increased with the increase of voltage, thus the corrosion performance of colored films is improved.