Grain Growth in Graphene: Novel Aspects in Two Dimensions

石墨烯中的晶粒生长：二维的新颖方面

• 批准号: 1615952
• 负责人: John Wilber
• 金额: $ 24.73万
• 依托单位: University of Akron
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-08-15 至 2022-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1615952&HistoricalAwards=false
• 关键词: Grain; Growth; Graphene; Novel; Aspects

This award supports a collaboration among three investigators on the modeling, analysis, and simulation of the behavior of sheets of graphene and similar materials interacting with other sheets or substrates. A graphene sheet is a single-atom-thick macromolecule of carbon atoms arranged in a hexagonal lattice. Hailed as the first truly two-dimensional material, graphene has been intensively studied since 2004 when individual graphene sheets were first isolated, a Nobel-prize-winning achievement. This research is motivated in large part by the exceptional physical properties of graphene and its potential applications in engineering and materials science. Experimental work confirms that the novel electronic properties of graphene, as well as its optical and thermal properties, are strongly coupled to deformation, deviations from perfect crystallinity, and the presence of defects such as wrinkles and grain boundaries. The project will use mathematical modeling and scientific computation to study these phenomena. It will provide rigorous insight and fundamental scientific understanding supporting applications of graphene sheets and related carbon macromolecules to develop new materials and technologies.The particular focus of this research is on pattern formation and interface motion in various two- or three-dimensional nanoscale structures built from two-dimensional macromolecules of carbon atoms. The project addresses a collection of problems related to lattice registry effects in single and bilayer graphene sheets, carbon nanotubes, and other carbon nanostructures. The phenomena motivating this study include pattern formation and localized wrinkling driven by lattice and orientation mismatches between a graphene sheet and its supporting substrate, moire patterns in bilayer graphene, motion of grain boundaries in polycrystalline graphene, and polygonization and faceting in multi-walled carbon nanotubes. Several variational problems are considered; analyzing the minimizers of these problems will yield insight into the phenomena just mentioned. A part of the project is devoted to studying propagation of interfaces using gradient flow dynamics. Much of the research activity hinges upon deriving continuum models that retain lattice registry effects to describe weak van der Waals interactions in carbon nanostructures. Hence, an important part of this study is the rigorous justification of the atomistic-to-continuum procedure that leads to such continuum models. Understanding and perhaps controlling phenomena influenced by lattice registry in carbon nanostructures and recently developed van der Waals heterostructures is essential for the successful use of these structures in materials science and nanoscale device development.

该奖项支持三名研究人员在建模，分析和模拟石墨烯和类似材料与其他床单或底物相互作用的材料行为的合作中的合作。 石墨烯片是在六角形晶格中排列的碳原子的单原子大分子。 自2004年首次孤立的单个石墨烯片（这是诺贝尔奖赢得的成就）以来，石墨烯被誉为第一个真正的二维材料，被深入研究。 这项研究在很大程度上是由于石墨烯的出色物理特性及其在工程和材料科学中的潜在应用。 实验工作证实，石墨烯的新型电子特性及其光学和热性能与变形，与完美结晶度的偏差以及皱纹和晶粒边界等缺陷的存在密切相关。 该项目将使用数学建模和科学计算来研究这些现象。 它将提供严格的洞察力和基本的科学理解，并提供石墨烯片和相关碳大分子的支持应用，以开发新的材料和技术。这项研究的特别重点是在各种二维纳米尺度结构中建立的模式形成和界面运动。 该项目解决了与单一和双层石墨烯片，碳纳米管和其他碳纳米结构的晶格注册效应有关的问题的集合。 激励该研究的现象包括模式形成和局部皱纹，由石墨烯片及其支撑底物之间的晶格和方向不匹配，双层石墨烯中的Moire模式，多晶石墨烯中晶粒边界的运动，以及在多层壁处理的碳nanotubes中的多边形和配置。 考虑了几个变异问题；分析这些问题的最小化者将洞悉刚才提到的现象。 该项目的一部分致力于使用梯度流动动力学研究接口的传播。 许多研究活动取决于得出连续模型，该模型保留了晶格注册效应，以描述碳纳米结构中弱的范德华相互作用。 因此，这项研究的重要部分是对导致这种连续模型的原子到核孔程序的严格理由。 理解，也许是受到碳纳米结构中晶格注册中心的影响，最近开发的范德华异质结构对于成功使用这些结构在材料科学和纳米级设备开发中至关重要。