Combined Macroscopic and Nanoscopic Studies of the Photovoltaic Behavior of Organic Perovskite Materials

有机钙钛矿材料光伏行为的宏观和纳米相结合研究

• 批准号: 1505535
• 负责人: Jinsong Huang
• 金额: $ 48万
• 依托单位: University of Nebraska-Lincoln
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-07-01 至 2017-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1505535&HistoricalAwards=false
• 关键词: Combined; Macroscopic; Nanoscopic; Studies; Photovoltaic

Non-technical Description: Development of cost-effective photovoltaic cells is one of the long-term, clean energy solutions for clean energy, air pollution, and energy security. An ideal strategy is to achieve efficient photovoltaic cells via depositing a naturally abundant active layer using a low-cost, low-temperature process. Organic perovskites are emerging as photovoltaic materials characterized by their excellent crystallinity, large optical extinction coefficient, and a suitable bandgap. In the last several years, the organic perovskite-based photovoltaic devices have experienced a faster increase in efficiency than any other solar cell technology. However, the basic understanding on the mechanisms of the photovoltaic behavior of organic perovskites is still in its infancy. This project explores the fundamental mechanisms with the ultimate goal to process organic perovskite materials with superior physicochemical properties for solar cell applications, and thus contributes to the technological development of renewable energy sources. The educational activities are well integrated with the research including: (1) promoting research training and teaching in nanoscience and clean energy technology for graduates and undergraduate students; (2) involving K-12 student and Nebraska residents through open-to-the-public events, such as 'Sunday with a Scientist' and 'Nanocamp'.Technical Description: The goal of this project is to investigate, at both the macro- and nanoscopic levels, two of the most important fundamental aspects related to the physical mechanisms of photovoltaic behavior of the organolead trihalide perovskite materials: (1) the role of chlorine (Cl) concentration in enhancing the photovoltaic behavior through the increased carrier diffusion length, and (2) the origin of the switchable photovoltaic effect. This project builds upon the principal investigator's expertise on stable high-quality crystalline perovskite films and high-efficiency perovskite solar cell devices, control of preferential grain orientation by Cl incorporation, and the switchable photovoltaic effect. Scanning probe microscopy (including conducting atomic force microscopy, piezoresponse force microscopy and Kelvin probe force microscopy) and macroscopic testing techniques (such as transient photovoltage, transient photocurrent, impedance spectroscopy, steady photocurrent and dark-current measurements) are used to investigate the effect of grain size and orientation on charge generation, transport, and recombination in perovskite thin films and devices. A combination of nanoscale studies of perovskite solar cells provides information critically important for understanding the underlying physical mechanism of the photovoltaic effect and enhancement of the functionalities of the perovskite-based solar cell devices.

非技术描述：开发具有成本效益的光伏电池是清洁能源、空气污染和能源安全的长期清洁能源解决方案之一。一个理想的策略是通过低成本、低温的工艺沉积自然丰富的有源层来获得高效的光伏电池。有机钙钛矿以其优异的结晶度、大的光学消光系数和合适的带隙而成为新兴的光伏材料。在过去的几年里，有机钙钛矿基光伏设备的效率比任何其他太阳能电池技术都有了更快的提高。然而，对有机钙钛矿的光电行为机理的基本认识仍处于起步阶段。本项目探索有机钙钛矿材料的基本机理，最终目标是为太阳能电池应用加工具有优异理化性能的有机钙钛矿材料，从而为可再生能源的技术发展做出贡献。教育活动与研究相结合，包括：(1)促进研究生和本科生在纳米科学和清洁能源技术方面的研究培训和教学；(2)让K-12学生和内布拉斯加州居民参与到公开活动中，如“周日与科学家”和“纳米夏令营”。技术描述：本项目的目标是在宏观和纳米水平上研究与三卤化有机铅钙钛矿材料光伏行为的物理机制相关的两个最重要的基本方面：(1)氯（Cl）浓度通过增加载流子扩散长度来增强光伏行为的作用；(2)可切换光伏效应的起源。该项目建立在首席研究员在稳定的高质量钙钛矿晶体薄膜和高效钙钛矿太阳能电池设备，通过Cl加入控制优先晶粒取向以及可切换光伏效应方面的专业知识之上。利用扫描探针显微镜（包括导电原子力显微镜、压电响应力显微镜和开尔文探针力显微镜）和宏观测试技术（如瞬态光电压、瞬态光电流、阻抗谱、稳态光电流和暗电流测量）来研究钙钛矿薄膜和器件中晶粒尺寸和取向对电荷产生、输运和复合的影响。钙钛矿太阳能电池的纳米级研究为理解光伏效应的潜在物理机制和增强钙钛矿基太阳能电池器件的功能提供了至关重要的信息。