CAREER: CAS: Ultrafast Electron and Molecular Dynamics Investigations on 2D Nanostructured Photocatalytic Materials for the Generation of Fuels from Renewable Sources

需要从阳光中生产燃料，类似于绿色植物的光合作用，是全球能源需求不断增加的结果。利用可见光将水分解成氢和氧以及从二氧化碳（CO2）生成燃料是重要的目标。虽然已经进行了大量的研究来从太阳光生产燃料，但目前还没有有效的方法来大规模生产太阳能燃料。使用一种新的实验技术，中央佛罗里达大学的Mihai Vaida博士正在监测表面分子的超快反应，在光驱动反应期间产生原子和分子的实时电影。这项研究为光催化过程提供了独特的见解，并有助于开发新的高效光催化剂，以加快太阳能燃料的产生。该研究与教育计划相结合，以传达K-12，本科和研究生水平的可再生能源清洁燃料的重要性。该计划正在招募和指导STEM（科学/技术/工程/数学）学科的女性和代表性不足的少数民族学生。在化学部化学催化计划的资助下，中央佛罗里达大学的Vaida博士正在开发必要的实验和教育工具，以调查，理解和传播2D纳米结构光催化材料和反应机制的结果，这些材料和反应机制导致从可再生能源中产生太阳能燃料。采用泵浦探测光电子能谱结合极紫外（XUV）激光脉冲，该项目研究了光催化剂表面的电荷载流子动力学与飞秒分辨率，表面灵敏度和元素特异性。此外，泵浦-探测飞秒激光质谱结合XUV软电离在表面上破译的反应机制，通过检测的中间物种和最终产品的时间，质量和能量分辨率。研究了二维过渡金属二硫属化合物表面修饰金属颗粒后的水裂解反应以及CO2还原生成燃料分子的反应。为了支持该项目的更广泛影响，Vaida博士积极参与外联活动，并与高中教师合作开发以可再生能源为重点的教学模块。此外，还组织研讨会，培训本科生和研究生在纳米材料领域的可再生能源生产和存储。该奖项反映了NSF的法定使命，并已被认为是值得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的支持。

The need to produce fuels from sunlight, similar to photosynthesis used by green plants, is the result of increasing global energy demand. The decomposition of water into hydrogen and oxygen and the generation of fuels from carbon dioxide (CO2) using visible light are important goals. Although a great deal of research has been performed to produce fuels from sunlight, currently there are no effective methods to produce solar fuels at large scale. Using a novel experimental technique, Dr. Mihai Vaida of the University of Central Florida is monitoring the ultrafast reactions of molecules at surfaces, producing real-time movies of atoms and molecules during light-driven reactions. This research is providing unique insights into photocatalytic processes and helping the development of new, highly efficient photocatalysts to speed up solar fuel generation. The research is integrated with an educational program to communicate the importance of clean fuels from renewable sources at the K-12, undergraduate, and graduate levels. This program is recruiting and mentoring women and underrepresented minority students in STEM (science/technology/engineering/mathematics) disciplines. With funding from the Chemical Catalysis Program of the Chemistry Division, Dr. Vaida of the University of Central Florida is developing the experimental and educational tools required to investigate, understand, and disseminate results of 2D nanostructured photocatalytic materials and reaction mechanisms that lead to the generation of solar fuels from renewable sources. Employing pump probe photoemission spectroscopy in conjunction with extreme ultraviolet (XUV) laser pulses, this project investigates the charge carrier dynamics at the photocatalyst surface with femtosecond resolution, surface sensitivity, and element specificity. Moreover, pump-probe femtosecond-laser mass spectrometry in conjunction with XUV soft ionization at the surface is employed to decipher the reaction mechanisms through the detection of intermediate species and final products with time-, mass-, and energy resolution. The water-splitting reaction as well as reactions that lead to the formation of fuel molecules via CO2 reduction are studied on 2D transition metal dichalcogenides decorated with metal particles. To support the broader impacts of the project, Dr. Vaida is actively engaged in outreach activities and is working with high school teachers to develop teaching modules focused on renewable energy. In addition, workshops are organized to train undergraduate and graduate students in the field of nanomaterials for renewable energy production and storage.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.