Colloidal Atomic Layer Deposition (c-ALD): quest for atomic precision in nanomaterial synthesis

胶体原子层沉积 (c-ALD)：追求纳米材料合成中的原子精度

• 批准号: 1611331
• 负责人: Dmitri Talapin
• 金额: $ 42.02万
• 依托单位: University of Chicago
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-07-15 至 2019-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1611331&HistoricalAwards=false
• 关键词: Colloidal; Atomic; Layer; Deposition; ALD

Nanomaterials, small particles consisting of only several thousand atoms and of only a few billionths of a meter in diameter, offer many opportunities for transformative science and technological applications. However, the lack of atomic precision during fabrication of nanometer-sized crystals restricts the ability to harness all the power of this broad and diverse class of materials. For example, a collection of real nanoparticles is always non-uniform and comprises particles with some variation in size within the group. Dr. Talapin is investigating how to eliminate this size variation and enable atomic precision in synthesis of nanoscale materials. Many practical applications, from flat-panel televisions to photodetectors and solar cells, will benefit from highly uniform, nearly atomically precise nanomaterials. Dr. Talapin is developing a technique called colloidal atomic layer deposition (c-ALD) to control the solution-based synthesis of nanomaterials using a sequence of two complementary self-limiting surface reactions. This concept is inspired by the success of gas-phase atomic layer deposition (ALD), which is widely used in microelectronics and other fields. Dr. Talapin's research has broader societal impact since it is directly relevant to the development of new technologically-relevant materials and has the potential to solve a fundamental problem that limits the pace of development for this broad class of materials. Dr. Talapin mentors undergraduate and high school students by helping them gain research experience. An important aspect of his outreach program focuses on education enrichment via science clubs and science nights for the local underrepresented African-American and Hispanic K-12 populations on Chicago's South Side. This project also supports the development and distribution of nanoscience educational resources accessible to the general public on the Talapin Lab website at the University of Chicago. Dr. Talapin of the University of Chicago is supported by the Supramolecular and Nanochemistry (MSN) Program to develop colloidal atomic layer deposition (c-ALD) of nanoscaled materials with precise size dispersion. The project aims to eliminate inhomogeneous ensemble broadening by growing functional nanomaterials in a layer-by-layer fashion, starting from atomically defined clusters of different technologically important materials. The polydispersity of nanomaterials originates from a weak size dependence of the free energy related to the addition or removal of individual atoms to/from a nanoscale object. In this case, size distribution can only be controlled by kinetic factors. Both theoretical modeling and numerous experimental studies show that it would be difficult to improve homogeneity significantly by only kinetically controlling reaction products. Dr. Talapin is working on a paradigm-shifting approach for colloidal synthesis of nanomaterials with minimal, ideally no, size distribution. The goal is to establish means to thermodynamically control nanomaterials synthesis using a sequence of two complementary self-limiting surface reactions. This concept is inspired by the success of gas-phase atomic layer deposition (ALD) widely used in microelectronics and other fields. Preliminary studies show that the ALD concept can be implemented in solution and, when applied to colloidal nanomaterials, enables layer-by-layer growth of crystalline lattices with close to atomic precision. Eliminating polydispersity at the ensemble level is arguably one of the most important challenges in nanomaterial synthesis. One can draw an analogy between size distribution of nanomaterials and the polydispersity index (PDI) of polymers. The discovery of advanced living polymerization techniques, which nearly eliminate chain polydispersity, has been among the most important recent developments in macromolecular chemistry. Dr. Talapin incorporates activities with broader societal impact into his research program. He actively trains undergraduate and high school students in his lab by giving them research experience opportunities. He also develops course modules and nanoscience educational resources applicable to K-12 students which are accessible to the general public on the Talapin Lab website at the University of Chicago. These hands-on labs and experiments are also used in outreach and education enrichment events for the local underrepresented African-American and Hispanic K-12 populations in on Chicago's South Side.

纳米材料是仅由数千个原子组成、直径仅为十亿分之几米的小颗粒，为变革性的科学和技术应用提供了许多机会。然而，纳米晶体制造过程中原子精度的缺乏限制了利用这种广泛而多样化的材料的所有能力的能力。例如，真实纳米颗粒的集合总是不均匀的，并且包含组内尺寸有一些变化的颗粒。 Talapin 博士正在研究如何消除这种尺寸变化并在纳米级材料的合成中实现原子精度。从平板电视到光电探测器和太阳能电池，许多实际应用都将受益于高度均匀、接近原子精度的纳米材料。 Talapin 博士正在开发一种称为胶体原子层沉积 (c-ALD) 的技术，通过一系列互补的自限性表面反应来控制纳米材料的溶液合成。这一概念的灵感来自气相原子层沉积（ALD）的成功，该技术广泛应用于微电子和其他领域。 Talapin 博士的研究具有更广泛的社会影响，因为它与新技术相关材料的开发直接相关，并且有可能解决限制此类材料发展速度的基本问题。塔拉平博士通过帮助本科生和高中生获得研究经验来指导他们。他的外展计划的一个重要方面是通过科学俱乐部和科学之夜为芝加哥南区当地代表性不足的非裔美国人和西班牙裔 K-12 人群提供丰富的教育。该项目还支持开发和分发纳米科学教育资源，供公众在芝加哥大学 Talapin 实验室网站上访问。芝加哥大学的 Talapin 博士在超分子和纳米化学 (MSN) 计划的支持下，开发具有精确尺寸分散的纳米级材料的胶体原子层沉积 (c-ALD)。该项目旨在通过从不同技术重要材料的原子定义簇开始，以逐层方式生长功能纳米材料，消除不均匀系综展宽。纳米材料的多分散性源于与纳米级物体中单个原子的添加或去除相关的自由能的弱尺寸依赖性。在这种情况下，尺寸分布只能通过动力学因素来控制。理论模型和大量实验研究表明，仅通过动力学控制反应产物很难显着提高均匀性。 Talapin 博士正在研究一种范式转换方法，用于胶体合成具有最小尺寸分布（理想情况下没有尺寸分布）的纳米材料。目标是建立使用一系列互补的自限制表面反应来热力学控制纳米材料合成的方法。这一概念的灵感来自广泛应用于微电子和其他领域的气相原子层沉积（ALD）的成功。初步研究表明，ALD 概念可以在溶液中实现，并且当应用于胶体纳米材料时，可以实现接近原子精度的晶格逐层生长。消除整体水平的多分散性可以说是纳米材料合成中最重要的挑战之一。我们可以将纳米材料的尺寸分布与聚合物的多分散指数（PDI）进行类比。先进的活性聚合技术的发现几乎消除了链多分散性，是高分子化学领域最重要的最新发展之一。塔拉平博士将具有更广泛社会影响的活动纳入他的研究计划。 他在实验室积极培训本科生和高中生，为他们提供研究体验机会。他还开发了适用于 K-12 学生的课程模块和纳米科学教育资源，公众可以在芝加哥大学 Talapin 实验室网站上访问这些资源。这些实践实验室和实验还用于为芝加哥南区当地代表性不足的非裔美国人和西班牙裔 K-12 人群开展外展和教育丰富活动。

项目成果

Bright trion emission from semiconductor nanoplatelets

半导体纳米片的明亮三重离子发射

• DOI: 10.1103/physrevmaterials.4.056006
• 发表时间: 2020-05-15
• 期刊: Physical Review Materials
• 影响因子: 3.4
• 作者: Lintao Peng;M. Otten;A. Hazarika;I. Coropceanu;M. Cygorek;G. Wiederrecht;P. Hawrylak;D. Talapin;Xuedan Ma
• 通讯作者: Xuedan Ma