Collaborative Research: Control of Contact Friction of Van der Waals Heterostructures

合作研究：范德华异质结构接触摩擦的控制

• 批准号: 2306038
• 负责人: Rosa Espinosa-Marzal
• 金额: $ 35万
• 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: 2023
• 资助国家: 美国
• 起止时间: 2023-08-01 至 2026-07-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2306038&HistoricalAwards=false
• 关键词: Collaborative; Research; Control; Contact; Friction

Two-dimensional materials enable creating a new class of nanoscale material systems by vertical, layer-by-layer stacking, resulting in ‘van der Waals’ heterostructures. This project aims to investigate the structural-mechanical-electronic coupling of van der Waals heterostructures with the ultimate goal of enabling friction control at nanoscale contacts. Created knowledge will advance (1) the design of nano- and microelectromechanical devices serving commercial and U.S. security needs by removing the constraints of high friction as a long-standing hurdle for their functionality, and (2) emerging manufacturing methodologies based on van der Waals assembly. Progress in this field will improve the sustainability and efficiency of manufacturing processes and thus increase U.S. industrial productivity and competitiveness. The collaborative project will train two graduate research assistants. Student demographics at University of California Irvine provide an ideal opportunity for broadening participation in mechanics and nanotechnology and contributing to the education of a diverse STEM work force. The team will take advantage of this opportunity by recruiting students for research engagement at all levels and will provide opportunities for student exchanges between their labs. Findings of this research will be integrated as part of graduate courses at the two universities.It is hypothesized that tuning the structural-mechanical-electronic coupling in ‘van der Waals’ heterostructures will afford control of friction. This is expected because the charge transferred-induced interlayer excitons between the targeted transition metal dichalcogenides monolayers influence the corrugation of the potential energy landscape at the sliding interface. The objective of this hypothesis-driven project is thus to establish experimental and theoretical foundation for van der Waals heterostructures with tunable and controllable friction. The team will investigate (1) how the intrinsic structure (two-dimensional materials combination, stacking order, twist angle, interlayer coupling) of van der Waals heterostructures influences the coupling and friction; and (2) determine how extrinsic factors like strain and electric field effect structural, mechanical and electronic properties of van der Waals heterostructures, and thereby friction. The experimental toolset relies on a scalable approach to assemble van der Waals heterostructures with twist angle control; characterization by photoluminescence/Raman spectroscopy and second harmonic generation; and nanoscale friction measurements correlated with surface topography, adhesion, and stiffness maps. It is also expected that the effect of interlayer charge transfer will make friction less sensitive to oxidation, which will be tested using deliberately oxidized samples.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.

二维材料可以通过垂直，按层堆叠来创建新的纳米级材料系统，从而产生“范德华”异质结构。该项目旨在研究范德华异质结构的结构机械电极耦合，其最终目标是在纳米级接触处实现摩擦控制。创建的知识将推进（1）通过消除高摩擦的限制作为其功能的长期障碍，以及（2）基于Van der waals组装的新兴制造方法，将纳米和微机电设备设计为商业和美国安全需求。该领域的进展将提高制造过程的可持续性和效率，从而提高美国的工业产品和竞争力。该协作项目将培训两名研究生研究助理。加利福尼亚大学尔湾分校的学生人口统计提供了扩大机械和纳米技术的参与并为潜水员STEM劳动力的教育做出贡献的理想机会。该团队将通过招募学生在各个层面的研究参与度中利用这一机会，并为实验室之间的学生交流提供机会。这项研究的结果将作为两所大学的研究生课程的一部分融合。假设调整“范德华”异质结构中的结构机械电极耦合将有助于控制摩擦。这是可以预期的，因为电荷在靶向过渡金属二分法单层之间转移了诱导的层间激子，影响了滑动界面处势能景观的波纹。因此，这个假设驱动的项目的目的是为具有可调和受控摩擦的范德华异质结构建立实验和理论基础。该团队将研究（1）范德华异质结构的内在结构（二维材料组合，堆叠顺序，扭角，层间耦合）如何影响耦合和摩擦； （2）确定范德华异质结构的结构，机械和电子特性等外在因素如何以及摩擦。实验工具集依靠可扩展的方法来组装具有扭角控制的范德华异质结构。通过光致发光/拉曼光谱和第二次谐波产生来表征；和纳米级摩擦测量结果与表面形貌，粘合剂和刚度图相关。还可以预期，层间电荷转移的效果将使摩擦对氧化的敏感性降低，该奖项将使用故意氧化的样品进行测试。该奖项反映了NSF的法定任务，并认为值得通过基金会的智力优点和更广泛的影响审查标准通过评估来进行评估。