Addressing Dynamic Donor:Acceptor and Electrode Interfaces in Organic Bulk-Heterojunction and Perovskite Solar Cells Under Device-Operating Condition

解决器件工作条件下有机体异质结和钙钛矿太阳能电池中的动态供体：受体和电极界面

• 批准号: 1438181
• 负责人: Bin Hu
• 金额: $ 36.59万
• 依托单位: University of Tennessee Knoxville
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-10-01 至 2019-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1438181&HistoricalAwards=false
• 关键词: Addressing; Dynamic; Donor; Acceptor; Electrode

Principal Investigator: Bin Hu Number: 1438181Nontechnical DescriptionThe sun represents the most abundant potential source of pollution-free energy on earth. Solar cells for the conversion of sunlight to electricity, also known as photovoltaic (PV) solar cells, suffer from a variety of complicated electrical processes during their operation that lower the overall solar energy conversion efficiency. This project will develop and use a novel technique based on magnetic field measurements to probe these electrical processes at material interfaces within two major classes of photovoltaic devices, organic polymer based photovoltaic (OPV) solar cells, and perovskite material based semiconductor solar PV cells, while these devices are in actual operation. OPV devices offer promise because they can be made from relatively inexpensive organic polymer materials, and perovskite materials offer promise because they are obtained from minerals abundant in the earth?s crust and have relatively high solar energy conversion efficiencies. Fundamental understanding of the useful and non-useful photovoltaic processes at material interfaces within these PV materials will suggest materials synthesis pathways and device engineering that can potentially lead to increased solar energy conversion efficiency in both PV device classes. The proposed activities will also offer interdisciplinary opportunities to enhance class teaching, research training opportunities for students from under-represented groups in science and engineering, and outreach activities for high-school students on the topic of organic polymer based solar cells. Technical DescriptionIn a photovoltaic (PV) device, when a photon from sunlight is absorbed and converted into an electron-hole pair, there are several loss mechanisms which prevent the charge from being carried away from the device as electric current, resulting in lowered solar energy conversion efficiency. The overall goal of this project is to gain a fundamental understanding of these recombination loss mechanisms at material interfaces though a unique magnetic field measurement technique. Specifically, the project will make measurements of magnetic field induced photocurrent and photo-induced capacitance to probe the binding energy and charge transfer states of the dynamic donor/acceptor interface in excitonic organic polymer based photovoltaic (OPV) devices, and the electrode interface non-excitonic perovskite thin-film photovoltaic devices respectively, using real operating devices under device operating conditions. The proposed research will gain insights on how to tune the electron-hole binding energies at the donor/acceptor interface for excitonic, bulk hetero-junction OPV devices through control of polarization and energy parameters, and on how to enhance the charge collection at the electrode interface in non-excitonic perovskite thin-film PV devices through dielectric effects. The research plan will focus on three tasks, including materials processing and device engineering to tune polarization and energy parameters at donor/acceptor and electrode interfaces, experimental studies on the useful and non-useful photovoltaic processes occurring at donor/acceptor and electrode interfaces, and finally, elucidation on the key parameters that control the electron-hole binding energies at the donor/acceptor interface and the charge collection at electrode interfaces. Fundamental understanding of the useful and non-useful photovoltaic processes at dynamic donor/acceptor and electrode interfaces will suggest materials synthesis pathways and device engineering that can potentially lead to increased solar energy conversion efficiency in both excitonic, bulk-hetero-junction OPVs and non-excitonic perovskite thin-film PV devices. With respect to education and broadening participation, the proposed activities will also offer interdisciplinary opportunities to enhance class teaching, research training opportunities for students from under-represented groups in science and engineering, and outreach activities for high-school students on the topic of organic polymer based solar cells.

主要研究人员：胡斌编号：1438181非技术描述太阳是地球上最丰富的潜在无污染能源。用于将太阳光转换为电能的太阳能电池，也称为光伏(PV)太阳能电池，在运行过程中遇到了各种复杂的电气过程，降低了太阳能的整体转换效率。该项目将开发和使用一种基于磁场测量的新技术，在两大类光伏器件-有机聚合物光伏(OPV)太阳能电池和钙钛矿型半导体太阳能光伏电池-内的材料界面上探测这些电子过程，而这些器件正在实际运行。开放式光伏设备之所以有希望，是因为它们可以由相对便宜的有机聚合物材料制成，而钙钛矿材料之所以有前景，是因为它们是从地球上丰富的矿物中获得的--S地壳，并且具有相对较高的太阳能转换效率。对这些光伏材料中材料界面上有用和无用的光伏过程的基本了解将为材料合成途径和器件工程提供建议，从而潜在地提高这两种光伏器件的太阳能转换效率。拟议的活动还将提供跨学科机会，以加强课堂教学，为科学和工程领域代表性不足群体的学生提供研究培训机会，并为高中生提供关于有机聚合物太阳能电池主题的外联活动。技术说明在光伏(PV)器件中，当来自太阳光的光子被吸收并转化为电子-空穴对时，有几种损耗机制防止电荷以电流的形式从器件中带走，从而导致太阳能转换效率降低。这个项目的总体目标是通过一种独特的磁场测量技术，从根本上了解材料界面上的这些复合损失机制。具体地说，该项目将测量磁场感生光电流和光生电容，分别探测激子有机聚合物光伏器件和非激子钙钛矿薄膜光伏器件中动态施主/受主界面的结合能和电荷转移状态，使用实际操作设备在器件运行条件下进行。这项研究将对如何通过控制极化和能量参数来调节激子、体异质结OPV器件施主/受主界面的电子-空穴结合能，以及如何通过介电效应增强非激子钙钛矿薄膜光伏器件电极界面的电荷收集获得新的见解。研究计划将集中在三个方面，包括材料加工和器件工程，以调节施主/受主和电极界面的极化和能量参数，实验研究发生在施主/受主和电极界面的有用和无效的光伏过程，最后阐明控制施主/受主界面电子-空穴结合能和电极界面电荷收集的关键参数。对动态施主/受主和电极界面上有用和无效的光伏过程的基本理解将为材料合成途径和器件工程提供建议，这些材料和器件工程可能导致激子、体异质结OPV和非激子钙钛矿薄膜光伏器件的太阳能转换效率提高。在教育和扩大参与方面，拟议的活动还将提供跨学科机会，以加强课堂教学，为科学和工程领域代表性不足群体的学生提供研究培训机会，并为高中生举办关于有机聚合物太阳能电池主题的外联活动。