本研究利用射頻磁控濺鍍，沉積純鐵薄膜於FTO導電玻璃上，再利用陽極處理法，將鐵薄膜放置在含有0.1M氟化銨及不同水含量之乙二醇溶液中，進行氧化及蝕刻反應以製備奈米棒陣列的氧化鐵薄膜。探討鐵薄膜製備陽極氧化鐵機制以及蝕刻液中水含量的改變對陽極氧化鐵薄膜物理特性及光電化學性質的影響及分析。 由X光繞射分析儀、X射線光電子能譜儀及元素分布圖等方式檢測，鐵薄膜經陽極處理可得氧化鐵結構，由掃描式電子顯微鏡及原子力顯微鏡觀察其多孔性陣列的表面形態及側面的柱狀結構。蝕刻液中水含量2、6、10、14vol%的溶液電導度分別為596、705、816及957μS/cm，對應的蝕刻孔洞大小分別為48.6、62.3、93及140nm。不同水含量製備陽極氧化鐵的能隙落在1.95到2.2 eV；以霍爾量測得知載子濃度範圍從4.695×1020到2.038×1021 cm-3；載子移動率從0.2854到1.217 cm2/V-sec。在光電化學量測，以1M的KOH水溶液為電解液，由Mott-Schottky分析得知薄膜平帶電位介於-0.7到-0.75V；以300W氙氣燈原，施加偏壓為0.5V時，最佳的光電流值為0.72mA/cm2。 In this study, iron films were deposited on fluorine-tin-oxide coated glass substrate. Using RF sputtering system, a self-oriented iron oxide nanorods array was obtained by anodization of iron thin films. Anodization was carried out in an ethylene glycol solution containing 0.1M NH4F and various water content. We investigated the mechanism of anodic iron oxide making by anodization of iron thin films, and the properties of anodic iron oxide samples anodized with different water content in the electrolyte. The results of X-ray diffraction、X-ray photoelectron spectroscopy and mapping image show that iron oxide can be obtained by anodization of iron thin films. SEM images show the porous morphology on the surface of samples. Nanorod like structure can be observed using cross-sectional SEM images. Surface roughness and nanorods array measurements were carried out using AFM. The conductivity of electrolyte vary from 596 to 957μS/cm by adjusting water content from 2 to 14vol%. The pore sizes of samples are 48-140nm respectively. The direct band gap of samples vary from 1.95 to 2.2 eV. Carrier concentrations of samples are in range of 4.695×1020 to 2.038×1021cm-3 using Hall measurement. The flat band potentials of samples are in the range of -0.7V to -0.75V by using Mott-Schottky measurement in 1M KOH solution. The maximum photocurrent density is 0.72mA/cm2 with a bias voltage of 0.5V (V vs. Ag/AgCl), under a 300W Xe lamp system.
