Reaction Limited Synthesis of Atomically-Defined Semiconductor Nanocrystals

原子定义的半导体纳米晶体的反应有限合成

• 批准号: 1710063
• 负责人: Mikhail Zamkov
• 金额: $ 35.08万
• 依托单位: Bowling Green State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-07-01 至 2021-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1710063&HistoricalAwards=false
• 关键词: Reaction; Limited; Synthesis; Atomically; Defined

Non-technical Abstract:Colloidal nanostructures are emerging as attractive candidates for low-cost processing of next-generation optical and electronic materials. Their characteristic size falls within the unique length scale where inorganic semiconductors exhibit tunable, molecular-like properties while retaining a good thermal and photo-stability. The chemical synthesis of semiconductor nanostructures typically results in a large variety of particle shapes and sizes, which negatively affects the ensuing device performance. To address this issue, the project aims to explore an alternative synthetic strategy for growing uniform, atomically-defined semiconductor nanoparticles. The innovation lies in employing chemical rather than thermal growth, which benefits from reaction-controllable, incremental steps in the particle formation. This strategy enables an unprecedented precision in controlling both the shape and the uniformity of semiconductor nanostructures. The development of a synthetic methodology for growing atomically-defined colloidal nanoparticles can potentially affect a wide range of emerging technologies relying on solution processing of semiconductors. It is expected to result in improved electrical and optical performance of materials for the solar fuel generation and solid state lighting. The educational aspects of this project are planned to focus on elucidating students through research activities and curriculum development.Technical Abstract:The project aims to explore a reaction-limited growth of colloidal semiconductor nanocrystals in an effort to achieve a controllable evolution of particle shapes and sizes. Nanocrystal synthesis is typically performed via thermal activation of precursors which benefits from a fast, low-defect crystallization. As a diffusion-limited growth mechanism, however, the hot-injection strategy makes it inherently difficult to control the nanoparticle size dispersion, ligand coverage, and the cation-to-anion ratio across the sample. As a result, distinct optoelectronic properties of individual nanoparticles become inhomogenously broadened in assemblies. The present strategy employs the sequential deposition of fully saturated cationic and anionic monolayers onto small-diameter clusters, which leads to focusing of particle sizes with the increasing diameter. Each ionic layer is grown via a colloidal analog of the atomic layer deposition to keep precursors and nanocrystals in separate phases. As a result, a self-limited monolayer deposition becomes very effective leading to stoichiometrically defined surfaces at each ion growth cycle. It is expected that an improvement in nanoparticle uniformity down to atomically precise structures is attainable through this strategy. An improved control over the nanoparticle size dispersion is likely to advance the development of light-emitting devices, whereas a well-defined surface composition could avail film-based nanocrystal applications (solar cells, transistors).

摘要：胶体纳米结构正在成为下一代光学和电子材料低成本加工的有吸引力的候选者。它们的特征尺寸落在独特的长度范围内，无机半导体在保持良好的热稳定性和光稳定性的同时表现出可调节的分子样性质。半导体纳米结构的化学合成通常会导致各种各样的颗粒形状和尺寸，这对随后的器件性能产生负面影响。为了解决这个问题，该项目旨在探索一种替代的合成策略来生长均匀的、原子定义的半导体纳米颗粒。创新之处在于采用化学生长而不是热生长，这得益于颗粒形成过程中反应可控的增量步骤。这种策略在控制半导体纳米结构的形状和均匀性方面实现了前所未有的精度。原子定义的胶体纳米颗粒生长的合成方法的发展可能会影响依赖于半导体溶液加工的广泛新兴技术。它有望改善太阳能燃料发电和固态照明材料的电学和光学性能。这个项目的教育方面计划集中在通过研究活动和课程开发来阐明学生。技术摘要：该项目旨在探索反应受限的胶体半导体纳米晶体生长，以实现颗粒形状和尺寸的可控演变。纳米晶体的合成通常是通过前驱体的热活化进行的，这有利于快速，低缺陷的结晶。然而，作为一种限制扩散的生长机制，热注入策略本身就难以控制纳米颗粒的尺寸分散、配体覆盖以及样品中的正负离子比。结果，单个纳米颗粒的不同光电特性在组装中变得不均匀地展宽。目前的策略是将完全饱和的阳离子和阴离子单层依次沉积到小直径的簇上，这导致颗粒尺寸随着直径的增加而集中。每个离子层是通过原子层沉积的胶体模拟物来生长的，以保持前驱体和纳米晶体在不同的相中。因此，在每个离子生长周期中，自限制单层沉积变得非常有效，导致化学计量学定义的表面。通过这种策略，纳米颗粒均匀性的改善可以达到原子精确的结构。改善对纳米颗粒尺寸分散的控制可能会促进发光器件的发展，而明确的表面组成可以利用基于薄膜的纳米晶体应用（太阳能电池，晶体管）。

项目成果

Just Add Ligands: Self-Sustained Size Focusing of Colloidal Semiconductor Nanocrystals

只需添加配体：胶体半导体纳米晶体的自我维持尺寸聚焦

• DOI: 10.1021/acs.chemmater.7b05165
• 发表时间: 2018
• 期刊: Chemistry of Materials
• 影响因子: 8.6
• 作者: Razgoniaeva, Natalia;Yang, Mingrui;Garrett, Paul;Kholmicheva, Natalia;Moroz, Pavel;Eckard, Holly;Royo Romero, Luis;Porotnikov, Dmitry;Khon, Dmitriy;Zamkov, Mikhail
• 通讯作者: Zamkov, Mikhail

Ion-Mediated Ligand Exchange and Size Focusing of Semiconductor Nanocrystals in Ligand-Saturated Solutions

配体饱和溶液中半导体纳米晶体的离子介导的配体交换和尺寸聚焦

• DOI: 10.1021/acs.jpcc.8b09215
• 发表时间: 2018
• 期刊: The Journal of Physical Chemistry C
• 作者: Kholmicheva, Natalia;Yang, Mingrui;Moroz, Pavel;Eckard, Holly;Vore, Abigail;Cassidy, James;Pushina, Mariia;Boddy, Anthony;Porotnikov, Dmitry;Anzenbacher, Pavel
• 通讯作者: Anzenbacher, Pavel

Thermally activated delayed photoluminescence from pyrenyl-functionalized CdSe quantum dots

• DOI: 10.1038/nchem.2906
• 发表时间: 2018-02-01
• 期刊: NATURE CHEMISTRY
• 影响因子: 21.8
• 作者: Mongin, Cedric;Moroz, Pavel;Castellano, Felix N.
• 通讯作者: Castellano, Felix N.

Enabling Narrow Emission Line Widths in Colloidal Nanocrystals through Coalescence Growth

• DOI: 10.1021/acs.chemmater.0c02874
• 发表时间: 2020-08
• 期刊: Chemistry of Materials
• 影响因子: 8.6
• 作者: James Cassidy;Cole Ellison;Jacob Bettinger;Mingrui Yang;P. Moroz;M. Zamkov

Double-Well Colloidal Nanocrystals Featuring Two-Color Photoluminescence

• DOI: 10.1021/acs.chemmater.7b02585
• 发表时间: 2017-09
• 期刊: Chemistry of Materials
• 影响因子: 8.6
• 作者: Natalia Razgoniaeva;Mingrui Yang;Cooper Colegrove;Natalia Kholmicheva;P. Moroz;H. Eckard;Abigail Vore;M. Zamkov