Two-Dimensional Layered Materials: Thermodynamic and Electrical Studies

二维层状材料：热力学和电学研究

• 批准号: 1409953
• 负责人: Leslie Allen
• 金额: $ 34.5万
• 依托单位: University of Illinois at Urbana-Champaign
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-09-01 至 2018-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1409953&HistoricalAwards=false
• 关键词: Two; Dimensional; Layered; Materials; Thermodynamic

Non-Technical AbstractWith support from the Solid State and Materials Chemistry Program in the Division of Materials Research, this project focuses on the basic scientific research of the properties of small crystals, the education of graduate and undergraduate students, and the further development of specialized scientific instruments such as nanocalorimetry. Using a newly discovered method, small, two-dimensional crystals of important materials will be grown and the melting temperature and conductive electronic properties will be investigated. The comprehensive study of these crystals will help develop breakthrough technologies in electronic materials and will provide a new understanding in biological membrane science. Further development of fast-scanning nanocalorimetry will also enhance the national infrastructure of scientific instrumentation. One of the important broader impact goals will be to increase participation in scientific and technical education through the building of devices (e. g. voltmeter and student nanocalorimeter measuring solar and battery heat) within the Native American community. Blackfeet Community College (BFCC) is located in Browning, Montana, which is the center for the Blackfeet Nation. The activities include a Science Summer Camp at the BFCC for the local students from the middle school, high school and the community college. The research team includes faculty and students from BFCC and the University of Illinois. Technical AbstractThe research team will prepare and characterize extremely thin crystals of two-dimensional layered materials (e.g. graphene and chalcogenides). One key attribute of all two-dimensional layered materials is the very weak van der Waal bonding between layers which allows the stacking of just a few layers. Special thermodynamic and electronic properties of these materials are only revealed if the crystals are extremely thin - as thin as a single layer of atoms or molecules. The focus of this project is to synthesize and characterize variations of silver alkanethiolates (AgSCn) and chalcogenides using a newly developed vapor deposition technique developed in the principal investigator's laboratory. The rigid central (Ag-S) plane of the AgSCn crystal controls crystal structure and is the key to its unique electronic properties. The synthesis activity focuses on incrementally decreasing the number layers of AgSCn (and chalcogenides) down to a single layer and decreasing the chain-length (n) of the alkane side chains down to one-carbon (AgSC1) thiloate. Using nanocalorimetry, which has the capability of measuring the melting of a single layer of atoms, the principal investigator will measure the melting characteristics of AgSCn crystals. The research team will also study the vertical and lateral conductive properties of the AgSCn and chalcogenides crystals using conductive probe atomic force microscopy. This dual synthesis and characterization approach will uncover the ultimate structural and electronic properties of these two material systems. New understanding of these systems is applicable to biological lipid membranes which are another example of single-layer materials, consisting of a single bilayer of organic molecules.

在材料研究部固体与材料化学项目的支持下，该项目侧重于小晶体性质的基础科研、研究生和本科生的教育以及专门科学仪器如纳米量热仪的进一步发展。 使用一种新发现的方法，将生长重要材料的二维小晶体，并研究其熔化温度和导电电子特性。 对这些晶体的全面研究将有助于开发电子材料的突破性技术，并将为生物膜科学提供新的认识。快速扫描纳米量热法的进一步发展也将加强国家科学仪器的基础设施。一个重要的更广泛的影响目标将是通过建立设备来增加对科学和技术教育的参与。G.测量太阳能和电池热量的伏特计和学生纳热量计）。 黑脚社区学院（BFCC）位于蒙大拿州的布朗宁，是黑脚民族的中心。这些活动包括在BFCC为来自初中，高中和社区学院的当地学生举办的科学夏令营。研究团队包括来自BFCC和伊利诺伊大学的教师和学生。技术摘要该研究小组将制备和表征二维层状材料（例如石墨烯和硫属化物）的极薄晶体。 所有二维层状材料的一个关键属性是层之间非常弱的货车德瓦尔键合，其允许仅堆叠几层。 这些材料的特殊热力学和电子性质只有在晶体非常薄的情况下才能显示出来-薄如单层原子或分子。本项目的重点是合成和表征银烷硫醇盐（AgSCn）和硫属化物的变化，使用新开发的气相沉积技术在主要研究者的实验室开发。 AgSCn晶体的刚性中心（Ag-S）平面控制晶体结构，并且是其独特电子性质的关键。 合成活动的重点是将AgSCn（和硫属化合物）的层数逐渐减少到单层，并将烷烃侧链的链长（n）减少到一碳（AgSC 1）硫代酸盐。 使用纳米量热法，它具有测量单层原子熔化的能力，首席研究员将测量AgSCn晶体的熔化特性。研究小组还将使用导电探针原子力显微镜研究AgSCn和硫属化物晶体的垂直和横向导电特性。 这种双重合成和表征方法将揭示这两种材料系统的最终结构和电子性质。 对这些系统的新理解适用于生物脂质膜，其是单层材料的另一个例子，由有机分子的单个双层组成。