NSF/DMR-BSF: Artificial Semiconductor Nanocrystal Molecules for Charge Carrier Separation

NSF/DMR-BSF：用于电荷载流子分离的人造半导体纳米晶体分子

基本信息

批准号：
2026741
负责人：
Eran Rabani
金额：
$ 37.5万
依托单位：
University of California-Berkeley
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：
2021-01-01 至 2024-12-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=2026741&HistoricalAwards=false
关键词：
NSF DMR BSF Artificial Semiconductor

项目摘要

NONTECHNICAL SUMMARYThis award supports theoretical and computational research with an aim to develop a fundamental understanding of the electronic and optical properties in a newly developed family of semiconductor nanocrystals using novel computational methods. Semiconductor nanocrystals are nano-sized (of the order of one billionth of a meter) particles, each containing hundreds to thousands of atoms arranged in a regular framework as in a solid semiconductor such as silicon. These nanocrystals are often referred to as artificial atoms. Remarkably, their chemical and physical properties, such as the color they emit, are flexibly tunable merely by changing their size, unlike real atoms. This has led to their widespread use as building blocks in diverse devices, e.g. to enrich color and enhance energy saving characteristics of the most advanced display screens. In this project, the research team will greatly extend the functionality of semiconductor nanocrystals by taking advantage of their artificial atom character. Carefully tailored semiconductor nanocrystals, serving as artificial atoms, will be combined with others to create a new family of artificial molecules. The particular focus of the project is the investigation of how positive and negative charges, which are created upon light absorption, separate from each other in such artificial molecules. Spatially separating the positive and negative charges in a semiconductor is central for harvesting solar energy (e.g. in solar cells) and transforming it into other, useful forms of energy in a clean and sustainable manner. Working in collaboration with an experimental group, the PI and his research team will focus their theoretical and computational research on understanding the mechanisms of charge separation as a function of the artificial molecules' atomic structure, composition and physical dimensions, and help design new artificial molecules made of semiconductor nanocrystals with desirable functionalities.This project will generate computational tools and fundamental understanding whose utility extends beyond the specific materials investigated. The research will serve as a basis for understanding the basic mechanisms of charge transfer in nanostructures and for designing new photocatalytic and photovoltaic devices that involve light induced charge separation. The project will involve the training of undergraduate and graduate students at the interdisciplinary interface of materials chemistry and engineering. The PI will also organize a summer school at the Telluride Science Research Center focused on modern electronic structure techniques. The lectures given by national and international experts in this school will be converted into online open-access videos for further dissemination of the educational material.TECHNICAL SUMMARYThis award supports theoretical and computational research with an aim to develop a fundamental understanding of the electronic and optical properties in a newly developed family of colloidal quantum dot heterodimers using state-of-the-art stochastic electronic structure techniques. The research team will focus on questions regarding (i) the mechanism of charge transfer at the nanometer scale, (ii) how to control the charge separation efficiencies by changing the dimensions and composition of materials, and (iii) how to model such complex quantum-dynamical models at the minimal model that accounts for all necessary physical processes. Validation of the computational approach will be based on quasiparticle excitations as well as neutral single- and multi-particle excitations. The validated models will then be used to explore the interplay of length scales and timescales on charge transfer mechanisms. The project will also focus on the role of changing the size of the donor/acceptor colloidal quantum dots and the neck connecting them and explore the interplay of Auger- vs. Marcus-like charge transfer mechanisms.This project will generate computational tools and fundamental understanding whose utility extends beyond the specific materials investigated. The research will serve as a basis for understanding the basic mechanisms of charge transfer in nanostructures and for designing new photocatalytic and photovoltaic devices that involve light induced charge separation. The project will involve the training of undergraduate and graduate students at the interdisciplinary interface of materials chemistry and engineering. The PI will also organize a summer school at the Telluride Science Research Center focused on stochastic electronic structure techniques. The lectures given by national and international experts in this school will be converted into online open-access videos for further dissemination of the educational material.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.

非技术摘要这一奖项支持理论和计算研究，目的是使用新型的半导体纳米晶体系列使用新型的计算方法来发展对电子和光学特性的基本理解。半导体纳米晶体是纳米大小的（数十亿分之一）的颗粒，每个粒子都包含在常规框架中排列的数百至数千原子，如固体半导体（如硅）。这些纳米晶体通常被称为人造原子。值得注意的是，与真实原子不同，它们的化学和物理特性（例如它们发出的颜色）仅通过改变大小而灵活地调节。这导致了它们广泛用作各种设备的构件，例如丰富颜色并增强最先进的显示屏屏幕的节能特性。在这个项目中，研究团队将通过利用其人工原子特征来大大扩展半导体纳米晶体的功能。精心量身定制的半导体纳米晶体（作为人造原子）将与其他人结合使用，以创建一个新的人造分子家族。该项目的特定重点是研究在这种人工分子中彼此分离的正面和负电荷是如何产生的。在半导体中，空间分离正电荷和负电荷对于收集太阳能（例如在太阳能电池中）并以干净可持续的方式将其转化为其他有用的能量形式是核心。与实验组合作，PI和他的研究团队将把他们的理论和计算研究集中在理解电荷分离的机制上，作为人工分子的原子结构，组成和物理维度的功能，并有助于设计新的人工分子，这些新人工分子由具有优质的纳米纳米纳米晶体构成，并构成了特定的计算。调查。该研究将作为理解纳米结构中电荷转移的基本机制的基础，并设计涉及光诱导电荷分离的新的光催化和光伏设备。该项目将涉及材料化学和工程跨学科接口的本科和研究生的培训。 PI还将在校尿素科学研究中心组织一所暑期学校，重点是现代电子结构技术。 The lectures given by national and international experts in this school will be converted into online open-access videos for further dissemination of the educational material.TECHNICAL SUMMARYThis award supports theoretical and computational research with an aim to develop a fundamental understanding of the electronic and optical properties in a newly developed family of colloidal quantum dot heterodimers using state-of-the-art stochastic electronic structure techniques.研究团队将重点介绍有关（i）纳米尺度上电荷转移机制的问题，（ii）如何通过更改材料的尺寸和组成来控制电荷分离效率，以及（iii）如何在所有必要的物理过程的最小值模型上对这种复杂的量子模型进行建模。计算方法的验证将基于准粒子激发以及中性的单粒子激发。然后，经过验证的模型将用于探索电荷传输机制上长度尺度和时间尺度的相互作用。该项目还将重点关注改变供体/受体胶体量子点的大小以及将它们连接起来的颈部的作用，并探索螺旋桨与Marcus类似Marcus的电荷转移机制的相互作用。此项目将产生计算工具和基本理解，其实用性超出了所研究的特定材料。该研究将作为理解纳米结构中电荷转移的基本机制的基础，并设计涉及光诱导电荷分离的新的光催化和光伏设备。该项目将涉及材料化学和工程跨学科接口的本科和研究生的培训。 PI还将在校尿素科学研究中心组织一所暑期学校，重点是随机电子结构技术。该学校的国家和国际专家的讲座将转换为在线开放式视频，以进一步传播教育材料。该奖项反映了NSF的法定任务，并被认为是值得通过基金会的智力优点评估来支持的，并具有更广泛的影响。