Modulating the Adhesion, Friction and Lubrication Characteristics of Few-Atom Thick Materials in Aqueous Environment over Several Length Scales

在多个长度尺度上调节水环境中少原子厚材料的粘附、摩擦和润滑特性

基本信息

批准号：
1904216
负责人：
Rosa Espinosa-Marzal
金额：
$ 45万
依托单位：
University of Illinois at Urbana-Champaign
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2019
资助国家：
美国
起止时间：
2019-08-15 至 2024-07-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1904216&HistoricalAwards=false
关键词：
Modulating Adhesion Friction Lubrication Characteristics

项目摘要

Two-dimensional (2D) materials are drawing significant attention because their atomic size results in unique material properties. Although water is often present in these systems and it significantly affects the microelectromechanical system or device performance, very little is known about the interfacial properties of 2D materials in the presence of water. This is partially due to the challenges involved in contamination-free, controlled processing of high quality 2D materials, which limits fundamental studies and applications. This project will study the science associated with the interfacial properties of 2D materials. Since the technology has direct applicability to micro and nano-scale devices, the research has the potential to impact the automotive, consumer electronic, aerospace and defense sectors, and therefore directly impacts economic welfare and national security. The research will contribute to the development of work force in the U.S. by training two graduate students research assistants. Further, the PIs? integrated education plan is designed to spark the early interest of K-12 students in STEM and inspire undergraduate and graduate students to further advance their interests in the intersection of 2D materials and surface science and engineering. In addition, the PIs will focus on broadening nano-engineering education by engaging student veterans and high school and minority students via summer research opportunities and field trips. The PIs will also actively pursue outreach activities, including interactive lectures and hands-on activities.In order to fill the knowledge gap of interfacial properties of 2D materials in aqueous environment, two major lines of research will be followed: (1) establish manufacturing methods for single- and few-layer graphene and molybdenum disulfide (MoS2) that afford control of their quality, the number of layers and substrate-induced doping characteristics over several length scales and (2) fundamentally comprehend, measure and model friction, adhesion, and lubrication by few-atomic thick materials in aqueous environment. The research hypothesis is that substrate-induced doping can be a means to modulate the interactions of few-atomic thick materials with water and ions, as well as their interfacial mobility, and therefore, it can be used to control electrical double layer, friction, adhesion and lubrication mechanisms. Preparation of contamination-free, single-crystalline graphene and MoS2 layers with controlled substrate-induced doping will enable careful study of interfacial properties of 2D materials in aqueous environment. Measurements with a surface forces apparatus (SFA) will provide thorough data of interfacial forces, which will be precisely modeled to quantify the effects of the substrate-induced doping. The ease of preparing samples for atomic force microscopy (AFM) will enable to also investigate substrate-induced doping via metal thin films, a higher number of ionic compositions and also to qualitatively compare the interfacial behavior of MoS2 and graphene with several other (exfoliated) 2D materials and with the bulk crystals. Ultimately, a theory for the relation between substrate-induced doping of 2D materials and their adhesive and frictional characteristics in the presence of water will be established.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

二维（2D）材料引起了人们的重大关注，因为它们的原子尺寸会产生独特的材料特性。尽管这些系统中通常存在水，并且会显着影响微机电系统或设备性能，但在水存在下2D材料的界面特性知之甚少。这部分是由于高质量2D材料的无污染，受控处理所涉及的挑战，这限制了基本研究和应用。该项目将研究与2D材料的界面特性相关的科学。由于该技术直接适用于微型和纳米级设备，因此该研究有可能影响汽车，消费电子，航空航天和国防部门，因此直接影响经济福利和国家安全。这项研究将通过培训两名研究生研究助理来为美国的劳动力发展做出贡献。此外，PI？综合教育计划旨在激发K-12学生对STEM的早期兴趣，并激发本科生和研究生，以进一步提高他们对2D材料与表面科学和工程的交集的兴趣。此外，PIS将通过夏季研究机会和实地考察与学生退伍军人和高中和少数族裔学生的参与来扩大纳米工程教育。 PI还将积极进行外展活动，包括互动讲座和动手活动。为了填补2D材料在水性环境中2D材料界面属性的知识空白，将遵循两项主要的研究线：（1）建立用于单层和少量二层二氧化碳（MOS2）的单层和钼的单层和数字的单位和数字的制造方法。尺度和（2）从根本上理解，测量和模型的摩擦，粘附和润滑在水性环境中很少有原子厚的材料。研究假设是，底物诱导的掺杂可以是调节几种原子厚材料与水和离子及其界面迁移率的相互作用的一种手段，因此可以用于控制电气双层，摩擦，粘附和润滑机制。用受控底物诱导的掺杂的无污染，单晶石墨烯和MOS2层的制备将仔细研究2D材料在水中环境中的界面特性。用表面力设备（SFA）进行测量将提供界面力的透彻数据，该数据将被精确建模，以量化底物诱导的掺杂的影响。制备原子力显微镜（AFM）样品的便捷性还可以通过金属薄膜，较高的离子组合物进行研究，还可以研究MOS2和石墨烯与其他几种（Exfoliated）的2D材料以及与Bulk Crystals的其他（Exfoliated）的界面行为进行定性比较。最终，将建立底物诱导的2D材料掺杂掺杂与它们在水存在下的粘合性和摩擦特征之间的关系的理论。该奖项反映了NSF的法定任务，并被认为是值得通过基金会的知识分子优点和更广泛的审查标准通过评估来通过评估来支持的。