Programmable Surfaces by Scalable Self-assembly of Particles Printed by Two-photon Polymerization

通过双光子聚合打印颗粒的可扩展自组装实现可编程表面

• 批准号: 2052251
• 负责人: Xun Wendy Gu
• 金额: $ 41.33万
• 依托单位: Stanford University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-05-01 至 2025-04-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2052251&HistoricalAwards=false
• 关键词: Programmable; Surfaces; Scalable; Self; assembly

Textured surfaces with micro-scaled features have many engineering applications such as self-cleaning, enhanced gripping and directional light scattering, etc. However, it is challenging to manufacture textured surfaces over a large area with high fidelity, needless to mention the issues with quality control, pattern complexity and special equipment needs, etc. This award supports fundamental research in self-assembling of countless polyhedral particles in a solution to achieve a wide range of micro-textured patterns. Beyond common geometry that can be fabricated using conventional lithography techniques, the unique innovation of this project is the use of two-photon polymerization to fabricate particles of complex shapes, which enable tunable in-plane and out-of-plane periodicities and out-of-plane protrusions in the self-assembly of micro-patterned surfaces. The studied self-assembled textured surfaces can potentially be programmed and achieve controllable wettability or be used as coatings, especially attractive for curved and/or delicate substrates in applications such as organic photovoltaics and wearable sensors. The educational activities consist of developing and implementing a particle self-assembly learning module for elementary school students, hosting a student, via summer internship, from a local Hispanic community college, and incorporating the topic of self-assembly into a graduate course on defects in crystalline solids.Using a three-dimensional printing technology, namely, two-photon polymerization, this project will fabricate micro-scaled particles for self-assembly into textured surfaces. Arrays on the order of 200,000 particles will be printed on a solid substrate, transferred to a liquid-filled well, and then self-assembled through a balance of sedimentation, diffusion, interparticle and particle-substrate interactions. Particles of different geometries will be investigated including tetrahedrons and square pyramids of varying sized as well as binary particle systems, to obtain a tunable feature height and periodicity formed at a millimeter scale. An optical microscope will be utilized to acquire video images of particle motions along the self-assembling time with automated image analyses to evaluate the quality of the self-assembled surface. The bond and body order parameters will be analyzed to understand the degree of uniformity that can be achieved under different processing conditions, and the types of defects generated during such a self-assembly process. Theoretical studies will include the Brownian motion modeled using the Einstein-Stokes equation and the energetic driving force modeled using the DLVO principle to design self-assembly experiments that are likely to succeed, and then compared against experimental results to gain new knowledge of what governs the self-assembly mechanisms.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.

具有微尺度特征的纹理表面具有许多工程应用，例如自清洁、增强抓握和定向光散射等。然而，大面积高保真度制造纹理表面具有挑战性，更不用说质量问题了控制、图案复杂性和特殊设备需求等。该奖项支持在解决方案中自组装无数多面体颗粒的基础研究，以实现各种微纹理图案。除了可以使用传统光刻技术制造的常见几何形状之外，该项目的独特创新是使用双光子聚合来制造复杂形状的粒子，从而实现可调节的面内和面外周期性以及面外周期性。 -微图案表面自组装中的平面突起。研究的自组装纹理表面可以进行编程并实现可控的润湿性或用作涂层，这对于有机光伏和可穿戴传感器等应用中的弯曲和/或精致基板特别有吸引力。教育活动包括为小学生开发和实施粒子自组装学习模块，通过暑期实习接待当地西班牙裔社区学院的学生，并将自组装主题纳入有关缺陷的研究生课程。结晶固体。该项目将使用三维打印技术，即双光子聚合，制造微型颗粒，用于自组装成纹理表面。大约 200,000 个颗粒的阵列将被打印在固体基质上，转移到充满液体的孔中，然后通过沉降、扩散、颗粒间和颗粒-基质相互作用的平衡进行自组装。将研究不同几何形状的粒子，包括不同尺寸的四面体和四角锥体以及二元粒子系统，以获得毫米级形成的可调特征高度和周期性。将利用光学显微镜获取自组装过程中粒子运动的视频图像，并进行自动图像分析，以评估自组装表面的质量。将分析键合和体序参数，以了解在不同加工条件下可以实现的均匀程度，以及在这种自组装过程中产生的缺陷类型。理论研究将包括使用爱因斯坦-斯托克斯方程建模的布朗运动和使用 DLVO 原理建模的能量驱动力，以设计可能成功的自组装实验，然后与实验结果进行比较，以获得关于控制自组装的新知识。自组装机制。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力优点和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

Diffusion of Anisotropic Colloidal Microparticles Fabricated Using Two‐Photon Lithography

使用双光子光刻技术制造的各向异性胶体微粒的扩散

• DOI: 10.1002/ppsc.202100033
• 发表时间: 2021-07-18
• 期刊: Particle & Particle Systems Characterization
• 影响因子: 2.7
• 作者: David Doan;John Kulikowski;X. Gu
• 通讯作者: X. Gu

Machine learning analysis of self-assembled colloidal cones

自组装胶体锥的机器学习分析

• DOI: 10.1039/d1sm01466h
• 发表时间: 2022-02
• 期刊: Soft Matter
• 影响因子: 3.4
• 作者: Doan, David;Echeveste, Daniel J.;Kulikowski, John;Gu, X. Wendy
• 通讯作者: Gu, X. Wendy

Mechanical nanolattices printed using nanocluster-based photoresists

使用基于纳米团簇的光刻胶印刷机械纳米晶格

• DOI: 10.1126/science.abo6997
• 发表时间: 2022-11
• 期刊: Science
• 影响因子: 56.9
• 作者: Li, Qi;Kulikowski, John;Doan, David;Tertuliano, Ottman A.;Zeman, Charles J.;Wang, Melody M.;Schatz, George C.;Gu, X. Wendy
• 通讯作者: Gu, X. Wendy