Probing and optimizing quantum dot confined states for next generation intermediate band solar cells

探测和优化下一代中能带太阳能电池的量子点受限态

• 批准号: 0933348
• 负责人: Harley Johnson
• 金额: $ 30.24万
• 依托单位: University of Illinois at Urbana-Champaign
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-08-15 至 2013-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0933348&HistoricalAwards=false
• 关键词: Probing; optimizing; quantum; dot; confined

0933348JohnsonSummaryTechnical Merit: Intermediate-band (IB) solar cells have the potential to convert sunlight to electricity with record efficiency. Perhaps the most promising approach to IB semiconductors is quantum dot (QD) arrays. In principle, these QD arrays would replace the intrinsic region in state-of-the-art p-i-n solar cells. Although this concept was originally proposed in the 1990s, the anticipated efficiency records have yet to be achieved. The performance to date has been limited by a lack of fundamental design rules for energy conversion processes in the context of QD confined states and minibands. In particular, an understanding of the influence of QD shapes, sizes, strain states, and QD/matrix interface uniformity on the formation of and interaction between QD confined states and minibands is needed. Furthermore, novel miniband architectures which enable optimum sunlight to electricity conversion efficiencies must be developed. The proposed approach involves a unique combination of state-of-the-art nanofabrication methods, measurements with unprecedented spatial resolution, and multi-scale simulations. The long-term objective of the work is to provide a set of design rules to optimize sunlight-to-electricity conversion in a wide variety of nanostructured materials. Several fundamental questions critical to the development of optimum sunlight-to-electricity conversion design rules will be addressed, including: what is the critical length scale at which the electronic states associated with a collection of point defects appear similar to those of a small QD? How do QD shapes and sizes influence the QD electronic states? How do interfacial disorder and strain influence the coupling of QD electronic states, as well as the formation of electronic mini-bands in two-dimensional and three-dimensional QD arrays? Which miniband architectures are needed to optimize the sunlight to electricity conversion efficiency? Using the unique combined expertise of the co-PIs in state-of-the-art nanofabrication, measurements with unprecedented spatial resolution, and multi-scale simulations, a set of design rules to optimize sunlight-to-electricity conversion in nanostructured intermediate band solar cells will be developed.Broader Impact: This research is expected to have a substantial impact on energy and sustainability. The PIs will also develop an outreach program in energy and sustainability. The outreach program will build partnerships in the local public high schools. This approach will lay the groundwork for a more ambitious outreach program developed by the co-PI in Ann Arbor, which has brought more than 30 local high school students to the UM campus for summer research internships. The PIs will develop a module, 'Materials for Solar Cells", to be incorporated into existing high school physics and chemistry courses. They will present this interactive and hands-on module to students from various backgrounds within several school systems. The module will draw on the excitement surrounding major new initiatives at UIUC and UM in sustainable energy research, and will serve to generate interest in engineering research.

0933348JohnSonsummaryTechnical优点：中型太阳能电池有可能以创纪录的效率将阳光转化为电。 IB半导体最有前途的方法也许是量子点（QD）阵列。原则上，这些QD阵列将取代最先进的P-I-N太阳能电池中的固有区域。尽管这个概念最初是在1990年代提出的，但预期的效率记录尚未实现。迄今为止，迄今为止的性能受到了在QD限制状态和迷你班的背景下缺乏能量转换过程的基本设计规则的限制。特别是，需要了解QD形状，大小，应变状态和QD/矩阵界面均匀性对QD限制状态和小型乘积之间相互作用的影响。此外，必须开发出最佳的阳光到电的新型迷你体系结构。所提出的方法涉及最先进的纳米制作方法的独特组合，具有前所未有的空间分辨率的测量以及多尺度模拟。这项工作的长期目标是提供一组设计规则，以优化各种纳米结构材料中的阳光到电动转换。将解决对最佳阳光到电动转换设计规则的发展至关重要的几个基本问​​题，包括：与点缺陷集合相关的电子状态的临界长度尺度是什么？ QD形状和尺寸如何影响QD电子状态？界面障碍和应变如何影响QD电子状态的耦合，以及在二维和三维QD阵列中的电子迷你频段的形成？需要哪些迷你架构来优化电力转化效率的阳光？利用Co-Pis在最先进的纳米构造中的独特综合专业知识，以前所未有的空间分辨率进行测量以及多尺度模拟，这是一套设计规则，以优化纳米结构中间的型中间带元单元的纳米结构中的阳光到电动转换的设计规则将开发出来的。 PI还将制定能源和可持续性的外展计划。外展计划将在当地的公立高中建立合作伙伴关系。这种方法将为Co-Pi在Ann Arbor制定的更雄心勃勃的外展计划奠定基础，Ann Arbor已将30多名当地高中生带到UM校园进行夏季研究实习。 PI将开发一个模块，即“太阳能电池的材料”，并将其纳入现有的高中物理和化学课程中。它们将向来自多个学校系统的各种背景的学生提供这个互动和动手模块。该模块将借鉴围绕UIUC的兴奋，以及在UIUC和UM中的重大新计划，并在可持续能源研究中产生了引起的引人入胜的发电机研究。