CAREER: Semiconductor Clusters: Chemistry at the Interface of Small Molecules and Quantum Dots

职业：半导体簇：小分子和量子点界面的化学

• 批准号: 1151172
• 负责人: Jonathan Owen
• 金额: $ 58.52万
• 依托单位: Columbia University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-04-01 至 2017-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1151172&HistoricalAwards=false
• 关键词: CAREER; Semiconductor; Clusters; Chemistry; Interface

This CAREER award by the Macromolecular, Supramolecular, and Nanochemistry (MSN) program supports work by Professor Jonathan Owen at Columbia University - endowed to understand the nucleation and growth of nanocrystalline semiconductors and their relationship to the conversion of precursor molecules. The core focus of the proposed work consists of two parts: (i) The kinetics and mechanisms of precursor conversion and their relationship to the crystallization of clusters and their subsequent conversion into larger nanocrystals, whether by assembly or atom-by-atom growth processes; (ii) To characterize and modify the surface structural features that cause surface state luminescence in these materials by systematic tailoring of cluster coordination chemistry. By studying atomically precise clusters, the assignment of specific structural elements responsible for trapping of excitons and investigations of crystal growth mechanisms all become possible with a level of detail not possible using traditional materials and methods. The broader impact of this proposal rests in its importance to classical models of surface tension and the nucleation of colloidal crystals. Understanding the origins of cluster stability will clarify how clusters are distinct from larger nanocrystals where the stability increases with the particles dimensions according to the Gibbs-Thompson relationship. This difference has important consequences for nanocrystal nucleation and growth mechanisms and is in stark contrast to the free energy arguments that underpin classical nucleation theory. The study of structure function relationships is integrated into a K-8 curriculum that teaches the importance of molecular structure to tangible aspects of everyday life. By integrating this context into the teaching of scientific concepts, chemical structure is made relevant to young students, promoting broad interest in scientific thinking.

该职业奖由高分子、超分子和纳米化学 (MSN) 项目颁发，支持哥伦比亚大学 Jonathan Owen 教授的工作，旨在了解纳米晶半导体的成核和生长及其与前体分子转化的关系。拟议工作的核心重点包括两部分：（i）前体转化的动力学和机制及其与团簇结晶及其随后转化为更大纳米晶体的关系，无论是通过组装还是逐个原子生长过程； (ii) 通过系统地调整簇配位化学来表征和修改导致这些材料中表面态发光的表面结构特征。通过研究原子级精确的团簇，负责捕获激子的特定结构元素的分配和晶体生长机制的研究都成为可能，其详细程度是使用传统材料和方法不可能实现的。该提议的更广泛影响在于其对表面张力和胶体晶体成核的经典模型的重要性。了解团簇稳定性的起源将阐明团簇与较大纳米晶体的区别，根据吉布斯-汤普森关系，较大纳米晶体的稳定性随着颗粒尺寸的增加而增加。这种差异对纳米晶体成核和生长机制具有重要影响，并且与支撑经典成核理论的自由能论证形成鲜明对比。结构功能关系的研究被纳入 K-8 课程中，教授分子结构对日常生活有形方面的重要性。通过将这一背景融入科学概念的教学中，化学结构与年轻学生相关，从而促进对科学思维的广泛兴趣。