CAREER: Understanding 2D confinement driven phase transitions of non-polar liquids

非技术文摘：摩擦磨损是一种普遍存在的现象，往往会造成巨大的能量损失和不利的环境影响。例如，由于摩擦损失，仅汽车应用就约占全球能源消耗的4%-5%。机械系统效率低下还会导致生命周期缩短，增加材料浪费和环境负担。为了应对这些挑战，润滑油行业需要高效、低污染的润滑油。二维(2D)材料，如原子薄层石墨和硫化钼，已成为保护发动机壁面的有前途的润滑油添加剂。2D材料的层状结构允许插入小分子，如碳氢油，这可以改变界面相互作用，调整机械和摩擦性能。在这个项目中，我们的目标是发展和利用原子力显微镜和振动光谱技术来研究埋藏界面上插层液体的物理行为和粘弹性性质。目标是调整插层相，以获得高度润滑性的表面。该项目还将为本科生和研究生提供跨学科和综合性的培训，培养能够加速材料发现和开发跨不同应用的技能。此外，该项目旨在促进摩擦学领域的对话和推广，以促进数据驱动的摩擦学进展的可访问和精选数据。技术摘要：该建议旨在研究液体，特别是烷烃的相行为是如何受到结构和热力学参数的影响的，当插入到2D材料产生的约束中时。探讨了围护结构、插层烷烃结构和衬底形态对插层过程及其界面性质的影响。通过这项研究，将在力谱和振动光谱方法方面取得进展，以量化埋藏界面上亚纳米插层的物理性质。通过将实验结果与模拟方法相结合，将实现对插层界面的力学和摩擦学行为的力学理解。这一研究成果将促进2D材料作为界面涂层在齿轮和发动机润滑以及纳米流体中的应用。此外，暑期研究培训机会将被开发，以鼓励未被充分代表的本科生从事跨学科研究，以开发下一代先进材料。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Non-technical Abstract:Friction and wear are ubiquitous phenomena which often lead to significant energy losses and adverse environmental impact. For instance, automotive applications alone account for approximately 4-5% of global energy consumption due to friction losses. Inefficient mechanical systems also result in shorter lifecycles, increasing material wastage and environmental burdens. To address these challenges, the lubricant industry requires efficient, low-pollutant lubricants. Two dimensional (2D) materials, such as atomically thin layers of graphite and molybdenum sulfide, have emerged as promising lubricant additives to protect engine walls. The layered structure of the 2D materials allows intercalation of small molecules, such as hydrocarbon oil, which can modify interfacial interactions and tune mechanical and frictional properties. In this project, we aim to advance and utilize the atomic force microscopy and vibrational spectroscopy techniques to investigate the physical behavior and viscoelastic properties of the intercalated liquids at the buried interfaces. The goal is to tune the intercalant phase for achieving highly lubricious surfaces. This project will also provide a training in interdisciplinary and integrative for undergraduate and graduate students, fostering skills that enable acceleration of material discovery and development across diverse applications. Additionally, this project aims to promote dialogue and outreach in the tribological community to facilitate accessible and curated data for data-driven advancements in tribology.Technical Abstract:This proposal aims to investigate how the phase behavior of liquids, specifically alkanes, is influenced by structural and thermodynamic parameters when intercalated within the confinement generated by a 2D material. The impact of the chemistry of confining walls, intercalant alkane structure, and the substrate morphology on the intercalation process and their interfacial properties will be explored. Through this study, advances in the methodologies of force spectroscopy and vibrational spectroscopy will be made to quantify the physical properties of sub-nanometer intercalant layers at the buried interface. By integrating experimental results with simulation methods, a mechanistic understanding of the mechanical and tribological behavior of intercalated interfaces will be achieved. The outcomes of this research will advance the applications of 2D materials as interfacial coatings in gear and engine lubrication, as well as in nanofluidics. Furthermore, summer research training opportunities will be developed to encourage underrepresented undergraduate students to engage in interdisciplinary research for the development of next-generation advanced materials.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.