DMREF/Collaborative Research: Graphene Based Origami and Kirigami Metamaterials

基于石墨烯的折纸和Kirigami超材料非技术描述：折纸和kirigami（'ori' =折叠，'kiri' =切割）的纸艺术提供了一个强大的框架来设计响应和可调的新材料。例如，一系列简单的切割可以将一张纸变成手风琴般的弹簧，或者一系列折叠可以将其转化为天鹅。事实上，许多生物组织会产生折叠和切割，让人想起折纸和kirigami，赋予它们独特而有用的机械特性。可以创造的形式似乎是无限的，这说明了将这种设计原则应用于纸张以外的材料的潜力。该项目将使用石墨烯（一种原子级薄的二维材料）作为纳米级纸张基础，将这些设计理念扩展到微米尺度。从半导体行业借鉴的光刻技术将被用来图案化石墨烯，并将采用各种方法来创建折叠，所有这些都被选择来实现特定的机械性能。重点是创造机械的“超材料”-材料的性质反映了折叠和切割的模式，而不是底层纸张的性质。 考虑到室温应用，理论上的努力将集中在热激活布朗运动在确定具有切割和折叠的石墨烯单层的材料特性方面的关键作用。这一灵感来自于纸艺的策略有可能从根本上改变微观世界的材料设计方式，并可能在从微型机器人到机械传感器和模拟生物“活性”组织的致动器等领域找到应用。技术描述：使用光刻技术，石墨烯片将被穿孔和切割，以创建具有指定机械性能的模块。这些模块将被组装以创建机械超材料，其对施加的应力，温度和其他环境信号的响应可以定制。该项目侧重于以下相互关联的目标：（a）通过实验测试目前对石墨烯热机械性能的预测及其对几何形状和边界条件的依赖性;（B）用切割的石墨烯片创建一个机械可编程模块单元库;（c）设计由基本石墨烯kirigami和origami模块组装而成的超材料，以实现特定功能;（d）设计一种新的石墨烯材料，以实现特定功能。（d）建立一种带有切口和褶皱的热激发原子薄膜理论，以指导实验和增进对基本原理的理解。这些目标将成为构建通用开源设计工具的基石，工程师可以使用该工具从基于折纸和kirigami的模块中组装材料，模拟其机械性能，并允许迭代设计工作流程。该工具将用于促进原子膜折纸和kirigami超材料的快速材料发现，开发和性能优化。

Graphene-Based Origami and Kirigami MetamaterialsNon-Technical Description: The paper arts of origami and kirigami ('ori' = fold, 'kiri' = cut) provide a powerful framework to design responsive and tunable new materials. For example, a simple series of cuts can turn a sheet of paper into an accordion-like spring, or a sequence of folds can convert it into a swan. Indeed, many biological tissues develop folds and cuts reminiscent of origami and kirigami that endow them with distinct and useful mechanical properties. The seemingly limitless number of forms that can be created speaks to the potential of exploiting such design principles for materials beyond paper. This project will extend these design ideas to the microscale using graphene, an atomically thin two dimensional material, as the nanoscale paper foundation. Lithographic techniques borrowed from the semiconductor industry will be used to pattern the graphene, and a variety of approaches will be employed to create folds, all chosen to realize a specific mechanical property. The focus is on creating mechanical 'metamaterials' - materials whose properties reflect the patterns of folds and cuts rather than the properties of the underlying paper. With room temperature applications in mind, the theoretical effort will focus on the crucial role of thermally-activated Brownian motion in determining the material properties of graphene monolayers with cuts and folds. This paper-arts-inspired strategy has the potential to fundamentally transform the way materials are designed for the micro-world and could find applications in areas ranging from micro-robotics to mechanical sensors and actuators that mimic biologically 'active' tissues.Technical Description: Using lithographic techniques, graphene sheets will be perforated and cut to create modules with prescribed mechanical properties. These modules will be assembled to create mechanical meta-materials whose response to applied stresses, temperature, and other environmental signals can be tailored. The project focuses on the following interrelated goals: (a) Experimentally testing current predictions for graphene's thermomechanical properties and their dependence on geometry and boundary conditions; (b) Creating a library of mechanically programmable modular units out of cut graphene sheets; (c) Designing meta-materials assembled out of the basic graphene kirigami and origami modules to achieve a particular function; (d) Creating a theory of thermally excited atomically thin membranes with cuts and folds, to guide experiments and improve understanding of the basic principles. These goals will form the cornerstone for building a general-purpose open source design tool that can be used by engineers to assemble materials out of the origami and kirigami based modules, simulate their mechanical properties, and allow for iterative design work flows. This tool will be used to promote rapid materials discovery, development, and property optimization of atomic membrane origami and kirigami metamaterials.