Artificial Molecular Machines and Devices

人造分子机器和装置

• 批准号: 0103559
• 负责人: James Stoddart
• 金额: $ 100万
• 依托单位: University of California-Los Angeles
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-08-15 至 2005-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0103559&HistoricalAwards=false
• 关键词: Artificial; Molecular; Machines; Devices

Under the influence of light, electricity, or chemical reagents, certain interlocked molecules, known as catenanes and rotaxanes-which comprise appropriately matched ring and dumbbell-shaped components-will perform motions (e.g., rotary and linear) at a molecular level reminiscent of the moving parts of macroscopic machines. Such molecular motors hold promise as the intelligent" building blocks for the construction of devices and machines. A team of chemists and engineers from two different institutions (UCLA and nearby CALTECH) will address the fundamental scientific issues surrounding the relationships between controllable molecular machines, nanoscate devices, and the predictable movements of machine components at a macroscopic level.The aims of this collaborative project-which focuses on the NSE RESEARCH THEME of Nanoscale Devices and System Architecture-are to (I) develop the template-directed synthesis (self-assembly) of interlocked molecules (switchable catenanes and rotaxanes) and interpenetrating supermolecules (addressable pseudorotaxanes) as a forerunner to (2) attaching them covalently to frameworks (e.g., silica, alumina) whose (3) synthesis (self-organization) must be established prior to (4) demonstrating the abilities of these machine-like (super)molecules to express different kinds of coherent movements (mainly linear but also possibly rotary ones) characteristic of macroscopic machines when (5) they are activated by chemicals (acids/bases or oxidizing/reducing agents) or electrons or light (redox and electron transfer processes) as a prelude to (6) transducing and amplifying the coherent molecular level movements into macroscopic motions.The specific objectives of the team are to demonstrate transduction of force and motion from the relative mechanical movements of the components present in catenanes, rotaxanes and pseudorotaxanes through the development-on the nanoscale level-of actuating materials and devices reminiscent of (1) engines, (2) levers, (3) muscles, and (4) valves.In thc first instance, we envisage constructing supramolecular two-stroke engines based on two-station pseudorotaxanes with the ring component lodged covalently in appropriately-sized silica pores, leaving the semi-dumbbell-shaped component to act as the piston. In the second example, we propose to design mechanical levers to amplify nanometer motions generated by suitable molecular or supramolecular machines. In the third instance, we propose to graft the ring and thread components of pseudorotaxanes onto separate carbon nanotubes using an aromatic polymer which we have demonstrated wraps itself helically around carbon nanotubes in order to realize artificial muscles and actuators. And, in the final example, we intend to develop molecular valves at the necks of suitably-sized silica pores, lined with pseudorotaxanes that can be induced to associate and dissociate (rings from threads) such that guest molecules located within the pores are, respectively, trapped or free to escape.The anticipated outcome of the proposed program of research includes (I) the synthesis of new molecular motors capable of operating as machines, (2) the synthesis of integrated power supplies for the machines, (3) a bottom-up and top-down integration of frameworks for the machines, (4) new fundamental understanding of forces, friction, etc., on the nanoscale, and (5) a group of students with both broad perspectives and individual expertise in nanoscicnce.With chemists and engineers working side-by-side, this highly integrated project seeks to transform molecular machines from being scientific curiosities into functioning nanosystems with technological potential, to enrich the education of both graduate and undergraduate students, and to promote the public awareness of nano-science and technology through community outreach.

在光、电或化学试剂的影响下，某些互锁的分子，称为索烃和轮烷--它们包括适当匹配的环状和哑铃状组分--将进行运动（例如，旋转和线性）在分子水平上使人联想到宏观机器的运动部件。这样的分子马达有望成为制造设备和机器的智能”积木“。来自两个不同机构的化学家和工程师团队（加州大学洛杉矶分校和附近的加州理工学院）将解决围绕可控分子机器，纳米器件，以及宏观层面上机器部件的可预测运动。这个合作项目的目标是（I）开发模板-作为先导的互锁分子（可转换的索烃和轮烷）和互穿超分子（可寻址的准轮烷）的定向合成（自组装）（2）将它们共价连接到骨架（例如，二氧化硅，氧化铝），其（3）合成（自组织）必须在（4）证明这些机器般的（超级）分子表达不同种类的连贯运动的能力之前建立（主要是线性的，但也可能是旋转的）宏观机器的特性，当（5）它们被化学物质激活时（酸/碱或氧化/还原剂）或电子或光（氧化还原和电子转移过程）作为（6）的前奏将相干的分子水平运动转换和放大为宏观运动。该团队的具体目标是演示力和运动从相对机械运动的转换。通过在纳米级水平上开发使人联想到（1）发动机、（2）杠杆、（3）肌肉和（4）阀门的致动材料和装置，使存在于索烃、轮烷和伪轮烷中的组分运动。在第一种情况下，我们设想构建基于两站伪轮烷的超分子二冲程发动机，其中环组分共价地适当地嵌入-尺寸的二氧化硅孔，留下半哑铃形的组件作为活塞。在第二个例子中，我们建议设计机械杠杆来放大由合适的分子或超分子机器产生的纳米运动。在第三种情况下，我们建议使用芳香族聚合物将伪轮烷的环和线组件接枝到单独的碳纳米管上，我们已经证明芳香族聚合物螺旋地缠绕在碳纳米管周围，以实现人工肌肉和致动器。在最后一个例子中，我们打算在适当大小的二氧化硅孔的颈部开发分子阀，并内衬可以诱导缔合和解离的伪轮烷（来自线的环）使得位于孔内的客体分子，分别，被困或自由逃脱。拟议的研究计划的预期成果包括（一）能够作为机器操作的新分子马达的合成，（2）机器的集成电源的合成，（3）机器框架的自下而上和自上而下的集成，（4）对力、摩擦等的新的基本理解，（5）一群在纳米科学方面既有广阔视野又有个人专长的学生。化学家和工程师并肩工作，这个高度综合的项目旨在将分子机器从科学好奇心转变为具有技术潜力的功能纳米系统，以丰富研究生和本科生的教育，并透过社区外展活动，提高市民对纳米科技的认识。