CAREER: Mapping the Chemical Reactivity of Metal Oxide Photocatalysts by Correlative Single-Molecule Fluorescence and Electron Microscopy

职业：通过相关单分子荧光和电子显微镜绘制金属氧化物光催化剂的化学反应性

• 批准号: 1753344
• 负责人: Bryce Sadtler
• 金额: $ 61.37万
• 依托单位: Washington University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-03-15 至 2024-02-29
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1753344&HistoricalAwards=false
• 关键词: CAREER; Mapping; Chemical; Reactivity; Metal

Nanocrystal photocatalysts are tiny, synthetic crystals that use light to accelerate chemical reactions. Photocatalysts that make fuels, such as methane, using only carbon dioxide, water and sunlight would have significant benefit to society. However, developing photocatalysts capable of sunlight-to-fuel conversion is a challenging problem that requires a fundamental understanding of the chemical reactions taking place on the nanocrystal surface. With support from the Macromolecular, Supramolecular and Nanochemistry Program of the NSF Division of Chemistry, Professor Sadtler at Washington University in St. Louis is developing microscopy methods to watch individual, light-driven reactions as they occur on single nanocrystal photocatalysts. Together, Professor Sadtler and his students are gaining new insights into why some atomic sites on the surface of nanocrystals are particularly active for catalysis. Professor Sadtler is also infusing his research into education. He is developing new courses that use atomic structure and chemical bonding as a basis to teach the frontiers of chemistry and materials science, as well as working with high school teachers and students in the St. Louis area.Metal oxide semiconductor nanocrystals with tunable stoichiometry are promising photocatalysts to produce liquid fuels through solar water splitting, partial methane oxidation, and the reduction of carbon dioxide. However, the contribution of specific structural and morphological features among individual catalyst particles to their ensemble activity is not well understood because each particle is different and possesses a variety of potential reaction sites. This project uses super-resolution fluorescence microscopy and redox-active fluorogenic probes to monitor photoinduced charge-transfer events on individual metal oxide nanocrystals with nanoscale spatial resolution. Correlation of the reactivity maps with the atomic resolution of scanning transmission electron microscopy performed on the same particles reveals how the distribution of oxygen vacancies in individual particles affects their reactivity. To further develop structure-activity relationships in metal oxide photocatalysts, the single-molecule, single-particle data are compared to measurements of bulk photocatalytic activity for methane oxidation and carbon dioxide reduction.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.

纳米晶体光催化剂是微小的合成晶体，利用光加速化学反应。仅利用二氧化碳、水和阳光来制造甲烷等燃料的光催化剂将为社会带来重大利益。然而，开发能够将阳光转化为燃料的光催化剂是一个具有挑战性的问题，需要对纳米晶体表面发生的化学反应有基本的了解。在美国国家科学基金会化学部高分子、超分子和纳米化学项目的支持下，圣路易斯华盛顿大学的萨特勒教授正在开发显微镜方法来观察单纳米晶体光催化剂上发生的单个光驱动反应。萨特勒教授和他的学生们对为什么纳米晶体表面的一些原子位点对于催化作用特别活跃有了新的见解。萨特勒教授也将他的研究融入到教育领域。他正在开发以原子结构和化学键为基础教授化学和材料科学前沿的新课程，并与圣路易斯地区的高中教师和学生合作。化学计量可调的金属氧化物半导体纳米晶体是有前景的光催化剂，可通过太阳能水分解、部分甲烷氧化和二氧化碳还原来生产液体燃料。然而，单个催化剂颗粒之间的特定结构和形态特征对其整体活性的贡献尚不清楚，因为每个颗粒都是不同的并且拥有各种潜在的反应位点。该项目使用超分辨率荧光显微镜和氧化还原活性荧光探针以纳米级空间分辨率监测单个金属氧化物纳米晶体上的光致电荷转移事件。对相同颗粒进行扫描透射电子显微镜的反应性图与原子分辨率的相关性揭示了单个颗粒中氧空位的分布如何影响其反应性。为了进一步开发金属氧化物光催化剂的结构-活性关系，将单分子、单颗粒数据与甲烷氧化和二氧化碳还原的本体光催化活性测量结果进行比较。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力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

Irreversibility in Anion Exchange Between Cesium Lead Bromide and Iodide Nanocrystals Imaged by Single-Particle Fluorescence

• DOI: 10.1021/acs.jpcc.0c08323
• 发表时间: 2020-12
• 期刊: Journal of Physical Chemistry C
• 影响因子: 3.7
• 作者: Dong Wang;Dongyan Zhang;B. Sadtler

Nanoscale Colocalization of Fluorogenic Probes Reveals the Role of Oxygen Vacancies in the Photocatalytic Activity of Tungsten Oxide Nanowires

• DOI: 10.1021/acscatal.9b04481
• 发表时间: 2020-01
• 期刊: ACS Catalysis
• 影响因子: 12.9
• 作者: Meikun Shen;Tianben Ding;Steven T. Hartman;Fudong Wang;Christina Krucylak;Zheyu;Wang;Che Tan

In Situ Imaging of Catalytic Reactions on Tungsten Oxide Nanowires Connects Surface–Ligand Redox Chemistry with Photocatalytic Activity

氧化钨纳米线上催化反应的原位成像将表面配体氧化还原化学与光催化活性连接起来

• DOI: 10.1021/acs.nanolett.2c00674
• 发表时间: 2022
• 期刊: Nano Letters
• 影响因子: 10.8
• 作者: Shen, Meikun;Ding, Tianben;Tan, Che;Rackers, William H.;Zhang, Dongyan;Lew, Matthew D.;Sadtler, Bryce
• 通讯作者: Sadtler, Bryce

Light-Driven, Facet-Selective Transformation of Cuprous Oxide Microcrystals to Hollow Copper Nanoshells

• DOI: 10.1021/acs.chemmater.9b02240
• 发表时间: 2019-09
• 期刊: Chemistry of Materials
• 影响因子: 8.6
• 作者: Chu Qin;Brandon M. Campbell;Meikun Shen;Tongyu Zhao;B. Sadtler

Fluorescence Microscopy of Single Lead Bromide Nanocrystals Reveals Sharp Transitions during Their Transformation to Methylammonium Lead Bromide

单溴化铅纳米晶体的荧光显微镜揭示了其转变为甲基溴化铅铵过程中的急剧转变

• DOI: 10.1039/c8tc06470a
• 发表时间: 2019
• 期刊: Journal of Materials Chemistry C
• 影响因子: 6.4
• 作者: Yin, Bo;Cavin, John;Wang, Dong;Khan, Daniel;Shen, Meikun;Laing, Craig;Mishra, Rohan;Sadtler, Bryce
• 通讯作者: Sadtler, Bryce