Materials World Network: Mapping Oxide Surface Reactivity Through Spacially-Resolved Atomic Interaction Forces

材料世界网络：通过空间分辨原子相互作用力绘制氧化物表面反应性

• 批准号: 0806893
• 负责人: Udo Schwarz
• 金额: $ 42万
• 依托单位: Yale University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-07-01 至 2012-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0806893&HistoricalAwards=false
• 关键词: Materials; World; Network; Mapping; Oxide

This is a collaborative research project between Yale University and the Universidad Autonoma de Madrid in Spain. The goal of the project is to characterize the chemical reactivity of individual surface atoms on transition metal oxide surfaces using non-contact atomic force microscopy with functionalized tips. For this purpose, a new technique capable of mapping the strengths of chemical interactions on the atomic scale will be developed through experimentation (carried out in Udo Schwarz' and Eric Altman's groups at Yale University) guided by theory (performed by Ruben Perez' group at the Universidad Autonoma de Madrid). The work builds upon recent demonstration of the ability to experimentally obtain the entire three-dimensional force field acting between a probe tip and surface in the short-range chemical forces regime with atomic resolution. Using this method with tips functionalized to expose electrophilic and nucleophilic head groups allows for the characterization and quantification of the key properties that govern oxide catalysis for individual cations and anions on the surface, in specific site geometries. The new method is initially applied to a comparison of the local chemical properties of Ti cations and O anions on the rutile (110) and anatase (001) surfaces, which, despite chemical and structural similarities, behave markedly differently chemically. For a fundamental understanding of the measured tip-sample interaction, the experimental program couples with a synergistic multi-scale theoretical effort that includes a quantum mechanical description of the short-range chemical forces, a classical description of the longer range dispersion forces, and molecular dynamics simulations of the influence of the forces on the probing geometry.The international collaboration of Yale University and the Universidad Autonoma de Madrid that is at the heart of this project provides a unique educational experience for the graduate and undergraduate students involved in the project. Through extended student exchanges during each year of the project, students are immersed in state-of-the-art experimental and theoretical efforts while being exposed to a truly international research environment. Also, further development of the method as a robust technique promises to impact other fields that are governed by local surface interactions including tribology, thin film growth, electronic device design, and the specific chemical interactions at the center of much of biology.

这是耶鲁大学和西班牙马德里自治大学的一个合作研究项目。该项目的目标是使用具有功能化尖端的非接触式原子力显微镜来表征过渡金属氧化物表面上单个表面原子的化学反应性。为此，将在理论指导下（由马德里自治大学的Ruben Perez小组进行），通过实验（由耶鲁大学的Udo施瓦茨和Eric Altman小组进行）开发一种能够在原子尺度上绘制化学相互作用强度的新技术。这项工作建立在最近的实验能力，以获得整个三维力场之间的探针尖端和表面的短程化学力制度与原子分辨率的演示。使用这种方法与尖端功能化暴露亲电和亲核头部基团允许的表征和量化的关键属性，管理氧化物催化的个别阳离子和阴离子的表面上，在特定的网站几何形状。新的方法最初应用于钛阳离子和O阴离子的金红石（110）和金红石（001）表面，尽管化学和结构的相似性，表现出显着不同的化学性质的局部化学性质的比较。为了从根本上理解测得的针尖-样品相互作用，实验程序与协同的多尺度理论努力相结合，该理论努力包括短程化学力的量子力学描述，长程色散力的经典描述，和分子动力学模拟力对探测几何的影响。耶鲁大学和自治大学的国际合作，马德里是该项目的核心，为参与该项目的研究生和本科生提供了独特的教育体验。通过在项目的每一年延长学生交流，学生沉浸在国家的最先进的实验和理论的努力，同时接触到一个真正的国际研究环境。此外，该方法作为一种强大的技术的进一步发展有望影响其他领域，这些领域由局部表面相互作用控制，包括摩擦学，薄膜生长，电子设备设计以及生物学中心的特定化学相互作用。