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

基本信息

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

项目摘要

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.

在化学结构，动力学和机制-A（CSDM-A）计划的支持下，Wake Forest University的Elham Ghadiri正在推进时间分辨的显微镜，并使用它们可视化基本光化学电荷转移过程如何在Solar Light Harvesting材料中受到微观局部的影响。然而，捕获这些电荷转移过程是一项挑战，因为它们发生在十亿分之一的时间中，而时间尺度在纳米长度尺度上的材料中从一个点到另一个点不等。 Ghadiri博士和她的学生正在开发飞秒的光学显微镜技术，这些技术可以可视化在用含有地球的材料制成的轻度收获半导体中的基本光化学反应。他们的发现可能会更好地理解在高度异质材料中发生的复杂光化学过程，并有助于制定设计标准，以实现未来清洁能源生成和存储应用中使用的有效的轻度收获材料。与WFU可持续发展计划合作，Ghadiri集团将使用基于研究的教育平台进行社区外展，旨在教育各个年龄段的人们有关可持续太阳能在日常生活中的作用，这是气候变化缓解的一个方面。 Ghadiri组将开发超快的显微镜和光谱法，以允许在复杂和异质太阳能转化材料中可视化基本光诱导的反应动力学。主要的重点是高度吸收且基于地球丰富元素的半导体，这使它们成为有希望的可持续能量转换应用的候选人。材料制造的太阳能电池的性能取决于独立发生并彼此竞争的超快和快速电子和质子转移反应的效率。超快的瞬态吸收和弥散反射显微镜将用于探测亚微米长度尺度和具有宽光谱覆盖率的超快时间尺度的动力学。该项目旨在提供对太阳能电池功能至关重要的电荷载体过程的深入时空分析。显微镜工具的进步推动了传统时间分辨光谱的限制是该作品的潜在广泛影响。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和更广泛影响的评估来评估的值得支持的。