Simulations of hydration lubrication between surfaces

表面之间水合润滑的模拟

• 批准号: 269080843
• 负责人: Professor Dr. Roland Netz
• 金额: --
• 依托单位: Institut für Theoretische Physik
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2015
• 资助国家: 德国
• 起止时间: 2014-12-31 至 2017-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/269080843?language=en
• 关键词: Simulations; hydration; lubrication; between; surfaces

Hydration lubrication describes a biologically and technically relevant range of lubrication phenomena between polar surfaces, characterized by an ultralow friction coefficient. It originates from strongly bound hydration layers formed around local surface charges. These hydration layers provide extraordinary lubrication properties that can resist also large loads. The experimental discoveries in the recent decade are still awaiting for thorough theoretical explanations and understanding. In order to illuminate the underlying mechanisms, we propose a study of the hydration lubrication phenomenon in terms of atomistic modeling. We plan to combine non-equilibrium flow as well equilibrium simulations with our novel techniques that enable to determine the exact hydration level at prescribed water chemical potential. In the first part we consider simple planar surfaces with controllable degrees of polarity and stiffness, which allows for a systematic study of the fundamental principles of friction forces. We proceed the study with experimentally relevant phospholipid membranes in fluid as well as gel phases. We intend to complement the results by investigating the underlying microscopic mechanisms based on hydrogen bonding dynamics, water order parameters, and membrane structure.

水合润滑描述了一种与生物学和技术相关的极性表面之间的润滑现象，其特点是超低摩擦系数。它起源于在局部表面电荷周围形成的强结合水合层。这些水合层提供了非凡的润滑性能，也可以抵抗大负荷。近十年来的实验发现仍有待于彻底的理论解释和理解。为了阐明其潜在的机制，我们提出了一种基于原子模型的水化润滑现象的研究。我们计划将非平衡流动和平衡模拟与我们的新技术结合起来，使我们能够在规定的水化学势下确定确切的水化水平。在第一部分中，我们考虑具有可控极性和刚度度的简单平面，这允许系统地研究摩擦力的基本原理。我们在流体和凝胶相中对磷脂膜进行了实验研究。我们打算通过研究基于氢键动力学、水序参数和膜结构的潜在微观机制来补充这些结果。

项目成果

Hydration Friction in Nanoconfinement: From Bulk via Interfacial to Dry Friction.

• DOI: 10.1021/acs.nanolett.7b02000
• 发表时间: 2017-09
• 期刊: Nano letters
• 影响因子: 10.8
• 作者: Alexander Schlaich;Julian Kappler;R. Netz

Analytical Interfacial Layer Model for the Capacitance and Electrokinetics of Charged Aqueous Interfaces.

• DOI: 10.1021/acs.langmuir.7b04171
• 发表时间: 2018-03
• 期刊: Langmuir : the ACS journal of surfaces and colloids
• 作者: Y. Uematsu;R. Netz;D. J. Bonthuis

Power-law electrokinetic behavior as a direct probe of effective surface viscosity

• DOI: 10.1016/j.cplett.2016.12.056
• 发表时间: 2017-02
• 期刊: Chemical Physics Letters
• 影响因子: 2.8
• 作者: Y. Uematsu;R. Netz;D. J. Bonthuis