Modeling the Formation of Self-Ordered Nanoporous Anodic Oxides

模拟自有序纳米多孔阳极氧化物的形成

• 批准号: 1000748
• 负责人: Kurt Hebert
• 金额: $ 28.03万
• 依托单位: Iowa State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-08-01 至 2014-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1000748&HistoricalAwards=false
• 关键词: Modeling; Formation; Self; Ordered; Nanoporous

The research objective of this award is to develop new methods for the rational design of highly ordered porous anodic oxide (PAO) films. These films are formed electrochemically by applying voltages to metals such as aluminum and titanium, in electrochemical cells. The films contain self-ordered hexagonal arrays of nanoscale pores, covering macroscopic areas. While much attention has focused on the use of PAO as templates for functional devices, these structures have been developed empirically, in the absence of robust understanding of processes controlling film growth. The goal of this research is to develop a fully predictive model of pore formation and self-ordering. The work will be guided by the concept that oxide material is transported by the combined influence of the electric field and mechanical stress. Experimental stress measurements will determine the operative balances of viscous, electrostatic and oxidation-induced stress governing interface motion in PAO films. Using this knowledge, descriptions of transport processes and driving forces will be formulated as a predictive simulation PAO growth, revealing the relations between electrochemical polarization, bath chemistry, and the dynamics of the self-ordering.If successful, the chemical-mechanical model of PAO formation will provide a fundamental basis for model-based design of self-organized porous anodic films. Thus, the model may permit rational manipulation of process conditions for high-rate fabrication of defect-free films, thus enhancing the commercial potential of PAO-based functional devices for solar energy conversion, catalysis, and biomedical applications. Student training will benefit from the unique aspects of this project: close integration of chemistry and mechanics; rigorous combination of a variety of experimental and modeling approaches; and on-site collaboration with a materials characterization group in England. Student training at Iowa State will take advantage of the strong presence of graduate and undergraduate programs promoting underrepresented groups, both at the Department and University levels.

该奖项的研究目标是开发合理设计高度有序的多孔阳极氧化（PAO）薄膜的新方法。 这些薄膜是通过在电化学电池中向铝和钛等金属施加电压以电化学方式形成的。 这些薄膜包含自序六边形纳米级孔阵列，覆盖宏观区域。 虽然人们的注意力集中在使用 PAO 作为功能器件的模板上，但这些结构都是凭经验开发的，缺乏对控制薄膜生长过程的深入了解。 这项研究的目标是开发一个孔隙形成和自排序的完全预测模型。这项工作将以氧化物材料通过电场和机械应力的综合影响进行传输的概念为指导。实验应力测量将确定控制 PAO 薄膜界面运动的粘性应力、静电应力和氧化诱导应力的操作平衡。 利用这些知识，传输过程和驱动力的描述将被公式化为 PAO 生长的预测模拟，揭示电化学极化、镀液化学和自排序动力学之间的关系。如果成功，PAO 的化学机械模型形成将为自组织多孔阳极薄膜的基于模型的设计提供基础基础。 因此，该模型可以合理控制工艺条件，以高速制造无缺陷薄膜，从而增强基于 PAO 的功能器件在太阳能转换、催化和生物医学应用中的商业潜力。 学生培训将受益于该项目的独特之处：化学和力学的紧密结合；多种实验和建模方法的严格结合；以及与英国材料表征小组的现场合作。 爱荷华州立大学的学生培训将利用研究生和本科生项目的强大优势，在系和大学层面促进代表性不足的群体。