Inter-American Materials Collaboration: Correlating Erbium Structure with Host Geometry in Doped Silicon Nanocrystals and Nanowires

这项美洲材料合作研究的重点是稀土掺杂硅纳米晶体和纳米线的基础研究，通过交换初级科学家，有针对性的跨学科研究培训，德克萨斯基督教大学化学系的Jeff Coffer和巴西圣保罗坎皮纳斯州立大学应用物理系的Leandro Tessler小组之间。该研究考察了纳米结构中稀土限制的基本原理。这是正在评估方面：主机晶体Si，平均Er 3+浓度，本地Er 3+协调，和平均Er 3+掺杂，可溶性纳米晶体的位置从热解反应隔离的大小依赖性。围绕乙硅烷（Si 2 H6）或硅烷（SiH 4）和稀土前体复合物在精心控制的条件下的高温热解，所得纳米结构通过光致发光（PL）光谱、紫外/可见光吸收光谱、透射电子显微镜/高分辨率电子显微镜进行表征（TEM/HREM）、拉曼光谱和扩展X射线吸收精细结构（EXAFS）测量。在巴西国家光源进行的EXAFS测量对于将局部铒结构与纳米结构的其他结构特征（包括其相关的物理行为）相关联至关重要。任何掺杂剂原子的位点特异性控制是下一代纳米级电子材料的合法结构控制中的核心和未回答的问题。国际合作为TCU材料化学的初级科学家提供了跨学科的培训经验，他们在巴西的应用物理学同行，并允许通过所有参与者的网络发展未来的研究机会。该奖项得到了材料研究部、国际科学与工程办公室以及数学和物理科学理事会多学科活动办公室的支持。

This Inter-American Materials Collaboration research focuses on fundamental investigations of rare earth-doped silicon nanocrystals and nanowires through an exchange of junior scientists, with directed interdisciplinary research training, between the groups of Jeff Coffer of the Texas Christian University Department of Chemistry and Leandro Tessler of the Department of Applied Physics at the State University of Campinas, Sao Paulo, Brazil. The research examines the fundamentals of confinement of the rare earth in the nanostructure. This is being evaluated in terms of: size dependence of the host crystalline Si, average Er 3+ concentration, local Er3+ coordination, and average Er3+ location for doped, soluble nanocrystals isolated from pyrolysis reactions. Centering on the high temperature pyrolysis of disilane (Si2H6 ) or silane (SiH4) and a rare earth precursor complex under carefully-controlled conditions, the resultant nanostructures are being characterized by photoluminescence (PL) spectroscopy, UV/visible optical absorption spectroscopy, transmission electron microscopy / high resolution electron microscopy (TEM/HREM), Raman spectroscopy, and Extended X-ray Absorption Fine Structure (EXAFS) measurements. EXAFS measurements performed at the Brazilian National Light Source are crucial to correlating local erbium structure with other structural features of the nanostructure, including its associated photophysical behavior. Site-specific control of any dopant atoms is a central and unanswered issue in the legitimate structural control of the next generation of nanoscale electronic materials. The international collaboration provides an interdisciplinary training experience to the junior scientists in materials chemistry at TCU, their counterparts in applied physics in Brazil, and permits the evolution of future research opportunities through networking for all involved. This award is supported by the Division of Materials Research, the Office of International Science and Engineering, and the Office of Multidisciplinary Activities in the Directorate for Mathematical and Physical Sciences.