Lithography on a nanosphere--an optical approach to arbitrarily patterned patchy particles

纳米球光刻——一种任意图案斑片粒子的光学方法

• 批准号: 1905527
• 负责人: Hans Robinson
• 金额: $ 49.65万
• 依托单位: Virginia Polytechnic Institute and State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-09-01 至 2024-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1905527&HistoricalAwards=false
• 关键词: Lithography; nanosphere; optical; approach; arbitrarily

PART 1: NON-TECHNICAL SUMMARYSelf-assembly -the spontaneous formation of well-defined ordered structures from simpler components- is a key mechanism that enables living organism to develop and grow in size and complexity. If self-assembly could be fully applied to technological problems, it would make it possible to create materials and devices that are well beyond the reach of other fabrication techniques, potentially revolutionizing many areas of materials science, electrical and chemical engineering, and other fields. One of the barriers preventing this is the difficulty in making starting components of sufficient complexity of the required quality for efficient self-assembly to take place. This project, which is supported by the Solid State and Materials Chemistry program at NSF, implements a new technique for making such particles. The particles are between a few hundred nanometers and a few micrometers in size and possess surface properties that can be patterned in nearly any configuration. These so-called "patchy particles" are excellent candidates for self-assembly starting components. The technique researchers at Virginia Polytechnic Institute and State University employ uses light to pattern spherical particles that are suspended in liquid, and it has very few restrictions of the distribution and configuration of the pattern fabricated on the spheres. On the level of basic science, this new route to patchy particles permits a more thorough exploration of self-assembly, which helps unravel the principles underlying this complex and only partially understood phenomenon. Because the same pattern can straightforwardly be projected onto any number of particles, it potentially makes the technique amenable to future production of patchy particle on an industrial scale. Thereby, this research may impact a wide range of fields, but some of the project's initial target structures may be particularly useful in the areas of flexible solar cells and in microrobotics. In addition to the scientific and potential technological advances described, students are benefitting from this research either by direct involvement in the project and mentoring, or through the insights it adds to the course curriculum of the new Nanoscience program at Virginia Polytechnic Institute and State University.PART 2: TECHNICAL SUMMARYWith this project, supported by the Solid State and Materials Chemistry program at NSF, researchers at Virginia Polytechnic Institute and State University develop a new paradigm for synthesizing patchy particles with a patch distribution that can be chosen with nearly complete freedom, and to demonstrate the self-assembly of these particles into well-defined structures, includes some that are not readily achievable with existing patchy particle fabrication techniques. The project applies an optical imaging technique to project identical patterns on any number of dielectric nanospheres and/or microspheres, where functionalization with ligands containing photocleavable protecting groups (PPGs) ensure that the optical patterns are transferred into functional groups such as amines, thiols, carboxyls, etc., which can then be modified further to produce patches with desired functionality. With functionalizations containing optically orthogonal PPGs (including o-nitrobenzyl, aminocoumarin, and BODIPY groups), multiple patch types with distinct properties can be produced through a single exposure, which is required for full implementation of the patchy particle concept. The basic building blocks for self-assembly are titania micro- and nanospheres for which a number of ligands are developed to suit the needs of the project, using phosphonic acid anchors to form stable bonds with the surface. Titania spheres are particularly useful for applications beneficial to society, such as photonic crystals for high efficiency dye-sensitized solar cells. Other potential applications include TiO2/Pt light-controlled micromotors, or their photocatalytic properties could be used to directly assist in the surface patch formation. As part of this project one or more patch-patch interactions (such as hydrophobic attraction, electrostatic binding, biotin-avidin binding etc.) are used to achieve several target structures ranging from relatively simple (linear chains, tetrahedra) to more challenging but previously demonstrated (Kagome lattices, pentapods) to structures of high interest that have yet to be assembled (icosahedra, diamond-structure colloidal crystals.) The patterning can be applied to particles in a bulk suspension and is therefore potentially scalable.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.

第1部分：非技术摘要自我组装 - 来自简单组件的定义明确有序结构的自发形成 - 是一种关键机制，使生物有机体能够在大小和复杂性上发展和生长。如果可以将自组装完全应用于技术问题，则可以创建远远超出其他制造技术范围的材料和设备，从而有可能彻底改变材料科学，电气和化学工程以及其他领域的许多领域。阻止这种情况的障碍之一是难以使所需质量足够复杂性的起始组件有效地进行自我组装。该项目得到了NSF的固态和材料化学计划的支持，它实现了一种制造此类颗粒的新技术。颗粒在几百纳米和几微米之间，并且具有几乎任何配置的表面特性。这些所谓的“斑点颗粒”是自组装起始组件的出色候选者。弗吉尼亚理工学院和州立大学的技术研究人员采用了光来模拟悬浮在液体中的球形颗粒，并且很少有对球体上制造的图案的分布和配置的限制。在基础科学的层面上，这种新的斑点粒子途径允许对自组装进行更彻底的探索，这有助于阐明这种复杂的原理，并且只能部分理解现象。由于相同的模式可以直接投影到任意数量的粒子上，因此它有可能使该技术在工业规模上适合将来生产斑块粒子。因此，这项研究可能会影响广泛的领域，但是该项目的一些初始目标结构可能在灵活的太阳能电池和微型机器人方面特别有用。除了所描述的科学和潜在技术进步外，学生还通过直接参与项目和指导而从这项研究中受益，或者通过洞察力增加了弗吉尼亚州理工学院新纳米科学课程的课程课程。与斑块分布合成斑块颗粒的范式，可以以几乎完全的自由选择，并将这些颗粒的自组装演示为定义明确的结构，其中包括一些在现有斑驳的颗粒制造技术中不容易实现的东西。该项目将光学成像技术应用于任何数量的介电纳米球和/或微球上相同的模式，在该模式下，使用包含可光透明保护组（PPG）的配体的配体功能化，确保光学模式确保将其转移到胺，胺，胆汁盒，袋中的功能中，以便将其转移到辅助范围内。随着含有光学正交PPG的功能化（包括O-硝基苯，氨基甲酰蛋白和BODIPY组），可以通过单个暴露产生多种具有不同特性的贴片类型，这是完整实现斑块粒子概念所必需的。自组装的基本构建块是钛微小和纳米球，开发了许多配体以适应项目的需求，使用磷酸锚锚与表面形成稳定的键。二氧化钛球对有益于社会的应用特别有用，例如用于高效染料敏感的太阳能电池的光子晶体。其他潜在的应用包括TiO2/PT光控制的微型电脑，或它们的光催化特性可用于直接帮助表面斑块形成。 As part of this project one or more patch-patch interactions (such as hydrophobic attraction, electrostatic binding, biotin-avidin binding etc.) are used to achieve several target structures ranging from relatively simple (linear chains, tetrahedra) to more challenging but previously demonstrated (Kagome lattices, pentapods) to structures of high interest that have yet to be assembled (icosahedra, diamond-structure colloidal晶体。）模式可以在散装悬浮液中应用于颗粒，因此具有潜在的可扩展性。该奖项反映了NSF的法定任务，并且使用基金会的知识分子优点和更广泛的影响审查标准，被认为是值得通过评估来支持的。