SusChEM: Mechanistic Studies of Photocatalytic Water-Splitting and CO2Reduction: The control of surface chemical reactivity and its effect on product distribution

SusChEM：光催化水分解和二氧化碳还原的机理研究：表面化学反应性的控制及其对产物分布的影响

• 批准号: 1465137
• 负责人: Siris Laursen
• 金额: $ 30.58万
• 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: 2015
• 资助国家: 美国
• 起止时间: 2015-07-01 至 2018-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1465137&HistoricalAwards=false
• 关键词: SusChEM; Mechanistic; Studies; Photocatalytic; Water

SusChEM: Mechanistic Studies of Photocatalytic Water-Splitting and CO2 Reduction: The control of surface chemical reactivity and its effect on product distributionDeveloping inexpensive catalytic materials that efficiently use solar energy to transform simple, readily-available substances into sustainably-produced fuels and chemicals is one of the grand challenges of the 21st century. This photocatalytic process is called "Artificial Photosynthesis" and is pursued for its promise of supplying cheap, clean energy and chemicals from carbon dioxide (CO2) and water (H2O). Currently, scientists do not completely understand how photocatalytic reactions can be controlled to produce the most desirable chemicals out of a large number of potential products. In this project, Dr. Laursen is developing an understanding of exactly how to control the surface chemical reactivity of Artificial Photosynthesis. A high level of control is critical if we are to produce the fuel or building-block chemicals selectively in an environmentally responsible fashion, as needed by our society. Dr. Laursen is actively engaged in outreach activities that build upon his research to promote engagement of students in science, technology, engineering and mathematics (STEM) disciplines. These activities, which include summer research internships in Dr. Laursen's laboratory, are directed at improving the education of promising high school seniors and women students and encouraging their interest in STEM careers. With funding from the Chemical Catalysis Program of the Chemistry Division, Dr. Siris Laursen of the University of Tennessee - Knoxville is developing a fundamental understanding of how the surface properties of Bi2S3, GaP, and CdS semiconductor photocatalysts dictate their catalytic activity and product selectivity in the reduction of CO2 and H2O to hydrogen, methane and simple oxygenated hydrocarbons. The surface-bound intermediates important in the mechanisms that determine catalyst efficacy are followed with in situ Diffuse Reflectance Infrared Fourier Transform spectroscopy (DRIFTS) to correlate the thermochemical stability of the various intermediate species with reaction rate and product selectivity. Also under investigation is how the chemical nature of surface bound hydrogen can be controlled to produce reduced organic molecules preferentially over molecular hydrogen or carbon monoxide. Density functional theory (DFT) calculations are carried out in parallel to the experimental work, and are used in support of structure-activity and composition-activity property determination. Dr. Laursen is actively engaged in STEM outreach programs focused on female student recruitment into the STEM fields and in high school student research internships, in support of the broader impacts of the project.

SusChEM：光催化水分解和二氧化碳还原的机理研究：表面化学反应性的控制及其对产品分布的影响开发廉价的催化材料，有效地利用太阳能将简单、容易获得的物质转化为可持续生产的燃料和化学品是其中之一21世纪的重大挑战。 这种光催化过程被称为“人工光合作用”，因其有望利用二氧化碳 (CO2) 和水 (H2O) 提供廉价、清洁的能源和化学品而受到人们的追捧。 目前，科学家们还不完全了解如何控制光催化反应，从大量潜在产品中生产出最理想的化学品。 在这个项目中，劳森博士正在深入了解如何控制人工光合作用的表面化学反应性。 如果我们要按照社会的需要，以对环境负责的方式有选择地生产燃料或基础化学品，那么高水平的控制至关重要。 Laursen 博士积极参与以他的研究为基础的外展活动，以促进学生对科学、技术、工程和数学 (STEM) 学科的参与。 这些活动包括在劳森博士实验室进行暑期研究实习，旨在改善有前途的高中生和女学生的教育，并鼓励她们对 STEM 职业的兴趣。 在化学系化学催化项目的资助下，田纳西大学诺克斯维尔分校的 Siris Laursen 博士正在对 Bi2S3、GaP 和 CdS 半导体光催化剂的表面特性如何决定其催化活性和产物选择性有一个基本的了解。将CO2和H2O还原为氢气、甲烷和简单的含氧烃。 在决定催化剂功效的机制中重要的表面结合中间体通过原位漫反射红外傅里叶变换光谱 (DRIFTS) 进行跟踪，以将各种中间体物种的热化学稳定性与反应速率和产物选择性相关联。 还在研究的是如何控制表面结合氢的化学性质，以优先于分子氢或一氧化碳产生还原的有机分子。 密度泛函理论（DFT）计算与实验工作并行进行，用于支持结构-活性和组成-活性性质的测定。 Laursen 博士积极参与 STEM 外展计划，重点关注招收女学生进入 STEM 领域和高中生研究实习，以支持该项目产生更广泛的影响。