CAREER: Understanding Quasicrystalline Superstructures Formed from Pyramidal Nanocrystals

职业：了解由金字塔形纳米晶体形成的准晶超结构

• 批准号: 1943930
• 负责人: Ou Chen
• 金额: $ 67.79万
• 依托单位: Brown University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-02-01 至 2025-01-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1943930&HistoricalAwards=false
• 关键词: CAREER; Understanding; Quasicrystalline; Superstructures; Formed

Non-Technical Summary:Crystalline materials are characterized by a structure with a regular, repeating pattern of atoms, while amorphous materials such as glass are disordered. Quasicrystalline (QC) materials are unusual in that they are ordered but not periodic, making them a fundamentally different category of materials which is neither a crystal nor a glass. The unique structure gives QC materials intriguing thermal, electrical, magnetic, optical and mechanical properties, making them useful for applications such as non-stick and thermally insulating coatings or corrosive-resistant and extremely strong materials for medical devices and surgical instruments. This CAREER award, supported by the Solid State and Materials Chemistry program within the Division of Materials Research, enables study of QC materials self-assembled from pyramid-shaped nano-sized particles (nanocrystals). The project includes detailed characterization of new QC materials’ structures and formation processes and also develops new characterization and growth methods that may be applicable to studying other soft matter assembly systems. The research offers ample fundamental and visual interest, as well as technological relevance, all of which are integrated into the PI’s education and outreach activities. YouTube movies with a jargon-free, storytelling style are created and promoted through various social media platforms. These videos take unique advantage of the connection between the beautiful and eye-catching QC patterns created by this fundamental study and real-world art, decoration and architectural design. Additionally, the project supports outreach to local high school students through an annual STEM Day. Technical Summary:This CAREER project, supported by the Solid State and Materials Chemistry program within the Division of Materials Research, integrates education and research on quasicrystalline (QC) superstructures assembled from pyramid-shaped nanocrystals (NCs). Self-assembly of NCs into novel superstructures is a promising approach for transporting nanoscopic properties into macroscopic materials to eventually enable highly efficient solar cells, low-energy-consumption lighting and displays, and more sensitive biological sensors. To realize these opportunities requires rational control over the formation of NC superstructures. Quasicrystals are ordered but not periodic and as such defy classification as either a crystal or a glass. The study of NC QC superlattices (QC-SLs) is in its infancy compared to efforts on conventional NC crystalline superstructures. It remains an outstanding question how NCs organize into these long-range ordered yet aperiodic lattices; methods to produce and characterize these unique materials are limited. To address these issues, the PI's group first synthesizes anisotropic pyramidal NCs and assembles them into QC superstructures. These materials are then characterized using combinations of in situ and ex situ real space methods (electron microscopies and tomography) complemented by reciprocal space measurements (electron diffraction and X-ray scattering). In addition to 2D superlattices, 3D QC supercrystals grown via microfluidics will be structurally characterized using a new super-crystallography technique. Together, these tools provide exquisite detail concerning the packing of these structures and specify the relative orientation of individual NCs. Such information clarifies how NC synthesis, superstructure formation and transformation work together to create QC superstructures. Results generated in this research are integrated into a series of outreach activities that target younger students and adults alike with compelling, visual stories designed to provoke interest in science and technology.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.

非技术摘要：结晶材料的特征是具有定期重复的原子模式的结构，而玻璃等无定形材料则无序。准晶（QC）材料是不寻常的，因为它们是订购的，但不是周期性的，因此它们是既不是晶体也不是玻璃的根本不同类别的材料。独特的结构使QC材料具有吸引人的热，电气，磁性，光学和机械性能，使其可用于不粘和热绝缘涂层或用于医疗设备和外科手术仪器的耐腐蚀性和极强材料。该职业奖在材料研究部内的固态和材料化学计划的支持下，可以研究从金字塔形纳米尺寸颗粒（纳米晶体）自组装的QC材料。该项目包括对新质量控制材料结构和形成过程的详细表征，还开发了可能适用于研究其他软材料组装系统的新特征和增长方法。该研究提供了充足的基本和视觉兴趣以及技术相关性，所有这些都融入了PI的教育和外展活动中。 YouTube电影具有无术语，讲故事的风格，并通过各种社交媒体平台创建和推广。这些视频具有独特的优势，即这项基本研究以及现实世界艺术，装饰和建筑设计创建的美丽和醒目的QC模式之间的联系。此外，该项目还支持在年度STEM日向当地高中学生推广。技术摘要：该职业项目在材料研究部内的固态和材料化学计划的支持下，整合了由金字塔形纳米晶体（NCS）组装的准晶（QC）上层建筑。 NC将NC的自组装成新型的上层建筑是一种有前途的方法，用于将纳米镜面特性转运到宏观材料中，最终使高效的太阳能电池，低能消耗照明和显示出更敏感的生物学传感器。要实现这些机会，需要对NC上层建筑的形成合理控制。排序的排序，但不进行周期性，例如晶体或玻璃等分类。与常规的NC晶体上层建筑相比，NC QC超级晶格（QC-SLS）的研究处于起步阶段。 NCS如何组织到这些远程有序却又有序的晶格中仍然是一个杰出的问题。生产和表征这些独特材料的方法受到限制。为了解决这些问题，PI的小组首先合成各向异性金字塔NCS，并将它们组装成QC上层建筑。然后，使用原位和原位真实空间方法（电子显微镜和断层扫描）的组合来表征这些材料，通过相互空间测量（电子衍射和X射线散射）完成。除2D超晶格外，通过新的超级结晶技术在结构上表征了通过微流体生长的3D QC超晶体。这些工具共同提供了有关这些结构包装的独家详细信息，并指定了单个NC的相对方向。此类信息阐明了NC合成，上层建筑形成和转换如何共同创建QC上层建筑。这项研究中产生的结果被整合到一系列外展活动中，这些活动针对年轻的学生和成人，他们都以引人注目的视觉故事来引起​​对科学和技术的兴趣。该奖项反映了NSF的法定任务，并通过使用基金会的知识分子优点和更广泛的影响标准来评估NSF的法定任务。

项目成果

Fast Lifetime Blinking in Compact CdSe/CdS Core/Shell Quantum Dots

紧凑型 CdSe/CdS 核/壳量子点的快速寿命闪烁

• DOI: 10.1021/acs.jpcc.1c03949
• 发表时间: 2021
• 期刊: The Journal of Physical Chemistry C
• 作者: Sun, Yonglei;Zhu, Hua;Jin, Na;Chen, Ou;Zhao, Jing
• 通讯作者: Zhao, Jing

Influence of local structures on the energy transfer efficiencies of quantum-dot films

• DOI: 10.1103/physrevb.102.035437
• 发表时间: 2020-07
• 期刊: Physical Review B
• 影响因子: 3.7
• 作者: Lintao Peng;Xuedan Ma;Hua Zhu;Ou Chen;Wei Wang

Bulk Grain-Boundary Materials from Nanocrystals

• DOI: 10.1016/j.chempr.2020.12.026
• 发表时间: 2021-02
• 期刊: Chem
• 影响因子: 23.5
• 作者: Yasutaka Nagaoka;M. Suda;Insun Yoon;N. Chen;Hanjun Yang;Yuzi Liu;B. Anzures;S. Parman;Zhongwu Wan

Synthesis of Ultrathin Perovskite Nanowires via a Postsynthetic Transformation Reaction of Zero-Dimensional Perovskite Nanocrystals

• DOI: 10.1021/acs.cgd.1c00118
• 发表时间: 2021-03
• 期刊: Crystal Growth & Design
• 影响因子: 3.8
• 作者: Hanjun Yang;Tong Cai;Lacie Dube;Katie Hills‐Kimball;Ou Chen

Quasicrystalline materials from non-atom building blocks

• DOI: 10.1016/j.matt.2022.09.027
• 发表时间: 2023-01
• 期刊: Matter
• 影响因子: 18.9
• 作者: Yasutaka Nagaoka;J. Schneider;Hua Zhu;Ou Chen