Polarization Mediated Atomic Interactions: Water and Pt on BaTiO3 (100)

非技术描述：过渡金属氧化物代表了一系列材料，这些材料在太阳能电池、后CMOS电子产品、通信系统和化学催化等应用中都能实现新器件。铁电化合物表现出与电子自旋、电荷和极化有关的极端特性，这为某些解决方案提供了创新途径。该项目使用原子分辨率工具来确定铁电表面与分子和金属团簇的相互作用。具体地说，水和铂与钛酸钡的相互作用是量化的。这项研究代表了这类材料中分子相互作用的第一个原子水平可视化。一所高中的暑期学院开设了纳米技术课程，以激发学生对科学领域职业生涯的兴趣，并为研究生开设了领导力课程，传授未来领导者所需的非技术技能。技术细节：铁电化合物表现出与电子自旋、电荷和极化相关的极端特性，具有使下一代能源、纳米电子和催化设备成为可能的潜力。该项目使用扫描隧道显微镜和光谱学以及其他表征工具来确定钛酸钡（100）表面有和没有金属团簇的分子吸收机制。钛原子配位对吸水率的影响是通过比较不同钛浓度下的一系列表面重构反应来确定的。通过比较不同取向域的隧穿光谱和铂金属团簇的隧穿光谱，考察了极化对水与铂金属团簇反应的影响。在光学照明下产生影响表面反应的载流子，并量化对水反应性的影响。将结果与理论计算进行比较，以便将局部电子结构与化学相互作用联系起来。研究结果揭示了薄膜生长、表面化学反应性和电子极化物理学的进展。一所高中的暑期学院开设了纳米技术课程，以激发学生对科学领域职业的兴趣，并为研究生开设了领导力课程，传授未来领导者所需的非技术技能。

NON TECHNICAL DESCRIPTION: Transition metal oxides represent a family of materials that is enabling new devices in applications ranging from solar cells to post CMOS electronics to communications systems to chemical catalysis. Ferroelectric compounds exhibit extreme properties related to electron spin, charge and polarization that suggest innovative pathways to some of these solutions. This project uses atomic resolution tools to determine the interactions of ferroelectric surfaces with molecules and metal clusters. Specifically, interactions of water and platinum with barium titanate are quantified. This research represents the first atomic level visualization of molecular interactions in this class of materials. A high school summer academy class in nanotechnology is offered to inspire interest in careers in science based fields and a leadership program for graduate students imparts the non-technical skills required in future leaders.TECHNICAL DETAILS: Ferroelectric compounds exhibit extreme properties related to electron spin, charge and polarization that have the potential to enable next generation devices in energy, nanoelectronics, and catalysis. This project uses scanning tunneling microscopy and spectroscopy in conjunction with other characterization tools to determine the mechanisms of molecular absorption on barium titanate (100) surfaces with and without metal clusters. The effect of Ti atomic coordination on water absorption is determined by comparing reactions on a series of surface reconstructions that vary in Ti concentration. The effect of polarization on reactions of water with Pt metal clusters is examined by comparing tunneling spectra over domains with different orientations with those of the clusters. Charge carriers that effect surface reactions are generated with optical illumination and the effect on water reactivity quantified. The results are compared to theoretical calculations in order to relate the local electronic structures to chemical interactions. The results inform advances in thin film growth, surface chemical reactivity and the physics of electronic polarization. A high school summer academy class in nanotechnology is class is offered to inspire interest in careers in science based fields and a leadership program for graduate students imparts the non technical skills required in future leaders.