Molecular Layers under Control

分子层受控

• 批准号: EP/I034610/1
• 负责人: Stuart Clarke
• 金额: $ 7.57万
• 依托单位: University of Cambridge
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2011
• 资助国家: 英国
• 起止时间: 2011 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FI034610%2F1
• 关键词: Molecular; Layers; under; Control

The goal of the proposed research is to investigate a new concept for preparing multi-component organic thin films with engineered molecular-scale organization and composition using liquid crystal (LC)-based inks combined with patterned anchoring alignment stamps. The central idea is to couple molecular order and composition in a multicomponent self-assembled monolayer (SAM) deposited from a nematic ink to a pattern on a stamp through an elastic strain field produced by competitive LC anchoring at the stamp- and SAM surfaces. The concept resembles strained heteroepitaxial growth at a solid-solid interface, except that the strain field is provided by a nematic LC, rather than the substrate, and results from anchoring and elastic forces, rather than an epitaxial mismatch. Despite the fact that LC elastic constants are much weaker than those of most solids, by selecting systems with an appropriate balance of energies we show how the LC can nevertheless have a significant influence, while affording considerable flexibility in structural and compositional control.The research is motivated by both fundamental interests and the practical importance of developing alternative approaches for creating chemically functionalized surfaces with designer architectures at nanometre to micron length scales. In addition to furthering our basic understanding of LC-surface interactions, phase behaviour, and pattern formation in organic thin films, the techniques to be developed in this work represent a step toward preparing materials with tailored physical and chemical properties, potentially useful for applications ranging from controlled wetting and adhesion, to chemical sensing and LC display technology.The concepts we propose to investigate represent a fundamentally new approach for using macroscopic influences to harness and control self-assembly at the molecular-scale, drawing upon ideas from LC science and multiphase systems. To carry out the work, an interdisciplinary collaboration is proposed between Prof. David Patrick, the Visiting Fellow and expert in LCs and LC-surface interactions, and Dr. Stuart Clarke, an expert in multiphase systems and the physical chemistry of organic thin films. Dr. Patrick, who is a Professor of Chemistry and Director of the Advanced Materials Science and Engineering Centre at Western Washington University, is a pioneer in unconventional uses of thermotropic LC solvents to prepare organized materials, while Clarke's group at Cambridge specialises in the molecular-scale properties of multi-component and multi-phase systems. The collaboration will combine these two areas of study.While at Cambridge, the Visiting Fellow will interact with other groups in the Chemistry Department and BP Institute, as well as those at several other universities across the UK, who will benefit from the expertise he brings in these novel approaches. Longer term, the proposed research will lay the foundations for a sustained collaboration that can continue after Patrick returns to his home institution.The proposed experimental programme would produce a comprehensive picture of the relationships between film composition and structural properties, LC forces, and the thermodynamics of monolayer formation in self-assembled monolayers deposited using LC inks. Although great deal of attention has been given to understanding the influence surfaces exert on LCs, including surfaces decorated with SAMs, the reverse situation-that is, LCs influencing surfaces-has hardly been considered at all. Taken together, the results of these experiments should provide a definitive assessment of the feasibility of LC-based inks, while deepening our understanding of the scientifically interesting and technologically important underlying phenomena.

本研究的目标是研究一种新的概念，利用液晶（LC）基油墨结合图案锚定对准印记，制备具有工程分子尺度组织和组成的多组分有机薄膜。该研究的核心思想是通过竞争性LC锚定在邮票和SAM表面产生的弹性应变场，将多组分自组装单层（SAM）从向列油墨沉积到邮票上的图案中，从而将分子顺序和组成偶联。这个概念类似于在固体-固体界面上的应变异质外延生长，除了应变场是由向列LC提供的，而不是衬底，并且是由锚定和弹性力产生的，而不是外延错配。尽管LC的弹性常数比大多数固体的弹性常数弱得多，但通过选择具有适当能量平衡的系统，我们展示了LC如何在结构和成分控制方面提供相当大的灵活性，同时如何产生重大影响。这项研究的动机是基于基本兴趣和开发替代方法的实际重要性，以在纳米到微米尺度上创建具有设计结构的化学功能化表面。除了进一步加深我们对有机薄膜中LC表面相互作用、相行为和模式形成的基本理解之外，这项工作中开发的技术代表了朝着制备具有定制物理和化学性质的材料迈出的一步，这些材料可能对控制润湿和粘附、化学传感和LC显示技术等应用有用。我们提出的研究概念代表了一种全新的方法，利用宏观影响来利用和控制分子尺度上的自组装，借鉴了LC科学和多相系统的思想。为了开展这项工作，访问学者、lc和lc表面相互作用专家David Patrick教授和多相系统和有机薄膜物理化学专家Stuart Clarke博士之间提出了跨学科合作。帕特里克博士是西华盛顿大学化学教授和先进材料科学与工程中心主任，他是非常规使用热致性LC溶剂制备有组织材料的先驱，而剑桥大学的克拉克小组则专门研究多组分和多相系统的分子尺度性质。这次合作将把这两个研究领域结合起来。在剑桥期间，这位访问学者将与化学系和BP研究所的其他小组以及英国其他几所大学的小组进行互动，这些小组将从他带来的这些新方法的专业知识中受益。从长远来看，拟议的研究将为帕特里克回到他的家乡机构后可以继续的持续合作奠定基础。所提出的实验方案将对薄膜组成与结构特性、LC力以及使用LC链接沉积的自组装单层形成的热力学之间的关系产生全面的了解。尽管很多人都关注于理解表面对LCs的影响，包括用地对空导弹装饰的表面，但相反的情况——即LCs影响表面——几乎没有被考虑过。综上所述，这些实验的结果将为lc基油墨的可行性提供一个明确的评估，同时加深我们对科学上有趣和技术上重要的潜在现象的理解。