摘要本文将 Ti 阳极氧化过程中的总电流分为离子电流和电子电流，首次推导出两个电流 的理论公式，定量地诠释了两个电流与阻挡层厚度、纳米管长度、表面形貌之间的内在 联系。结果表明，在常用的四个电压和四个温度下的氧化过程中，理论公式可以很好地 拟合所有实测的电流—时间曲线。将 TiO2 纳米管生长动力学的研究从定性水平提高到定 量水平。另外，基于电场平衡模型和“气泡模具”模型对纳米管之间的缝隙和“肋骨” 的成因提出了全新的解释。覆盖在纳米管上的表面层和电场分布的差异对缝隙的形成起 着决定作用。纳米管周围“肋骨”的形成是电解液间歇性渗入到缝隙底部，在电解液与 Ti 基体的界面上形成氧化物所致。并且创新性地提出了一种避免“肋骨”形成的方法。77968

毕业论文关键词 阳极氧化 TiO2 纳米管 电子电流 生长动力学 电解液

Title  Anodization of Ti Foils and Research in Formation Mechanism of TiO2 Nanotubes

Abstract In this paper, the theoretical expressions for the time dependent ionic current and electronic current are firstly derived to explore the anodizing process of Ti。 In this way, the ionic current and electronic current can be separated from the total current and be researched respectively。 Furthermore, these expressions systematically illustrate the quantitative relationship between the ionic/electronic current and TiO2-nanotubes morphology such as the thickness of barrier, the length of tubes and the diameter of the pores。 The anodizing current–time curves under different anodizing voltages and different temperatures are experimentally investigated in the anodization of Ti。 All of the current-transient plots can be fitted consistently by the proposed theoretical expressions。 These results can promote the research of kinetics from a qualitative to quantitative level。On the other hand, based on many experimental facts, new explanations for the gaps and ribs are presented。 An entire surface layer covered on the nanotubes plays a primary role on the formation of gaps and ribs。 The gaps result from the radial distribution of the electric field at the pore bottom。 No newly-formed oxide will exist along the gap direction, because the electric filed along the gap is the minimum。 The ribs result from the electrolyte entering into the wider gaps among the ATNTs due to the rupture of the entire surface layer。 The present viewpoint was demonstrated by an original micro-dam, which can block the electrolyte entering into the gaps and avoid the formation of ribs。

Keywords anodization TiO2  nanotubes electronic current growth kinetics electrolyte

本科毕业设计说明书 第 I 页

目次

1。绪论 1

1。1 阳极二氧化钛纳米管的研究背景 1

1。2 阳极二氧化钛纳米管的形成过程及相关化学反应 1

1。2。1 氧化初级阶段 1

1。2。2 多孔氧化膜的形成 2

1。2。3 多孔氧化膜的生长 3

1。3 阳极氧化参数对纳米管尺寸的影响 3

1。3。1 电解液 3

1。3。2 阳极氧化电压