CAREER: CAS: Broadband UV-NIR Ultrafast Photochemistry Imaged in Space and Time

职业：CAS：宽带 UV-NIR 超快光化学在时空成像

• 批准号: 2239539
• 负责人: Elham Ghadiri
• 金额: $ 65万
• 依托单位: Wake Forest University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-02-15 至 2028-01-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2239539&HistoricalAwards=false
• 关键词: CAREER; CAS; Broadband; UV; NIR

With support from the Chemical Structure, Dynamics, and Mechanisms-A (CSDM-A) program in the Division of Chemistry, Elham Ghadiri of Wake Forest University is advancing time-resolved microscopies and using them to visualize how the fundamental photochemical charge-transfer processes taking place in solar light-harvesting materials are affected by the microscopic structure of their local surroundings. Capturing these charge-transfer processes is challenging, however, as they take place in times approaching a millionth of a billionth of a second, and the time scales vary from one point to another in a material on nanometer length scales. Dr. Ghadiri and her students are developing femtosecond optical microscopy techniques that can visualize the fundamental photochemical reactions in light-harvesting semiconductors made from earth-abundant materials. Their discoveries could lead to a better understanding of complex photochemical processes that take place in highly heterogenous materials, as well as help to develop design criteria for efficient light-harvesting materials used in future clean energy generation and storage applications. In partnership with the WFU sustainability program, the Ghadiri group will engage in community outreach using research-based educational platforms designed to educate people of all ages about the role of sustainable solar devices in daily life as one aspect of climate change mitigation. The Ghadiri group will develop ultrafast microscopy and spectroscopy methods to allow the visualization of fundamental photoinduced reaction dynamics in complex and heterogeneous solar energy conversion materials. The primary focus is on semiconductors that are highly light-absorbing and that are based on earth-abundant elements, which makes them promising candidates for sustainable energy conversion applications. The performance of solar cells fabricated from the materials depends on the efficiency of ultrafast and fast electron and proton transfer reactions that occur independently, and in competition with each other. Ultrafast transient absorption and diffuse reflectance microscopies will be used to probe the dynamics on sub-micron length scales and ultrafast time scales with broad spectral coverage. The project aims to provide an in-depth spatiotemporal analysis of charge carrier processes that are central to solar cell function. The advancement of microscopy tools that push the limits of conventional time-resolved spectroscopy is a potential broader impact of the work.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.

在化学系化学结构，动力学和机制-A（CSDM-A）计划的支持下，维克森林大学的Elham Ghadiri正在推进时间分辨显微镜，并使用它们来可视化太阳光捕获材料中发生的基本光化学电荷转移过程如何受到当地环境微观结构的影响。然而，捕捉这些电荷转移过程是具有挑战性的，因为它们发生的时间接近十亿分之一秒的百万分之一，并且时间尺度在纳米长度尺度的材料中从一个点到另一个点变化。Ghadiri博士和她的学生正在开发飞秒光学显微镜技术，该技术可以可视化由地球上丰富的材料制成的集光半导体中的基本光化学反应。他们的发现可以更好地理解在高度异质材料中发生的复杂光化学过程，并有助于制定用于未来清洁能源发电和储存应用的高效捕光材料的设计标准。Ghadiri集团将与WFU可持续发展计划合作，利用基于研究的教育平台参与社区外联活动，旨在教育所有年龄段的人们了解可持续太阳能设备在日常生活中的作用，作为减缓气候变化的一个方面。Ghadiri小组将开发超快显微镜和光谱学方法，以实现复杂和异质太阳能转换材料中基本光致反应动力学的可视化。主要重点是高度吸光的半导体，这些半导体基于地球上丰富的元素，这使它们成为可持续能源转换应用的有希望的候选者。由这些材料制成的太阳能电池的性能取决于超快和快速电子和质子转移反应的效率，这些反应独立发生，并且相互竞争。超快瞬态吸收和漫反射显微镜将用于探测亚微米长度尺度和超快时间尺度上的动态，具有广泛的光谱覆盖范围。该项目旨在提供对太阳能电池功能至关重要的电荷载流子过程的深入时空分析。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

Ultrafast microscopy and image segmentation of spatially heterogeneous excited state and trap passivation in Cu2BaSnSSe3

• DOI: 10.1016/j.xcrp.2023.101601
• 发表时间: 2023-09
• 期刊: Cell Reports Physical Science
• 影响因子: 8.9
• 作者: Hannah Luebbering;A. Shafiee;B. Teymur;Yongshin Kim;D. Mitzi;E. Ghadiri

Nanosecond Diffuse Reflectance Spectroscopy for In-Situ Analysis of Electron Back-Recombination and Dye Regeneration in Fully Functional, Highly Efficient, Opaque Dye-Sensitized Solar Cell Devices

• DOI: 10.1021/acs.jpcc.3c05382
• 发表时间: 2023-11-20
• 期刊: JOURNAL OF PHYSICAL CHEMISTRY C
• 影响因子: 3.7
• 作者: Ghadiri，Elham;Moser，Jacques-E.
• 通讯作者: Moser，Jacques-E.