二氧化鈦奈米管熱處理之交流阻抗研究

Impedance Studies of Heat Treated Titanium Dioxide Nanotubes

劉陶仕(Tao-Shih Liu)

指導教授 ： 薛文景

國立臺北科技大學/工程學院/材料及資源工程系研究所/碩士(2011年)

https://doi.org/10.6841/NTUT.2011.00194

摘要

本研究主要是利用電化學交流阻抗分析法，對形成二氧化鈦奈米管後之鈦金屬試片在各種溫度下進行結構上之分析。實驗以加入0.5wt% NH4F的乙二醇(Ethylene Glycol，EG)溶液做為電解液，並將鈦試片置於陽極，鉑片置於陰極，以電壓40V、脈衝頻率50Hz作4小時的陽極處理，使其表面生成緻密氧化膜並具有奈米級孔洞之試片。然後，於不同溫度下作退火熱處理，使表面氧化膜由非晶質相(amorphous)去玻化為銳鈦相(anatase)及金紅石相(rutile)。實驗結果由SEM、XRD觀察其各種熱處理溫度下之形貌及性質。最後以電化學交流阻抗法 (EIS) 做分析比較。鈦試片在700℃時，開始析出費德曼針狀組織，可提高其抗腐蝕性；而經本研究陽極脈衝再於600℃下進行熱處理表面生成二氧化鈦奈米管之試片，可於試片上得到更穩定奈米管狀結構且使其抗腐蝕性增加。

關鍵字

電化學交流阻抗法 ； 二氧化鈦奈米管 ； 脈衝陽極處理 ； 熱處理 ； 非晶質相

並列摘要

In this study, the ATO (anodic titanium oxide) nanotubes formed on the surfaces of commercial titanium specimens were characterized by conducting the Electrochemical Impedance Spectrum (EIS) analysis for their structures. The pulse anodization was performed in the cell of 95% Ethylene Glycol and 0.5wt% NH4F electrolyte with titanium anode and platinum cathode. Experiments conditions were set with 40voltage of applied potential and 50Herzs of pulse frequency for four hours to have an ordered channel-array of (ATO) nanotubes formed on the electro-polished titanium samples. The nanotubes were heat treated from amorphous state to the devitrified anatase and rutile at annealing temperatures. The morphologies and properties of amorphous and crystalline of ATO nanotubes were employed by using Scanning electron microscope (SEM) and X-Ray Diffraction (XRD). The followed EIS data showed that higher corrosion resistance can be achieved at 700 ℃due to the precipitation of Widmanstatten structure, Furthermore, specimens having pulse anodized and 600 ℃ treated ATO nanotubes would increase their corrosion resistance. This is deduced that the formation of nano- tubular structure on the specimens of this work resulting a stable surface condition.

並列關鍵字

Electrochemical impedance spectrum analysis (EIS) ； Anodic titanium oxide (ATO) ； Pulse anodized ； Heat treatment ； Amorphous state

參考文獻

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