CAS-Climate: Atomically Resolved Single-Molecule Microscopy of Catalytic Intermediates in CO2 Reduction

CAS-Climate：二氧化碳还原催化中间体的原子分辨单分子显微镜

• 批准号: 2203589
• 负责人: Udo Schwarz
• 金额: $ 47.39万
• 依托单位: Yale University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-09-01 至 2025-08-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2203589&HistoricalAwards=false
• 关键词: CAS; Climate; Atomically; Resolved; Single

With support from the Chemical Measurement and Imaging (CMI) Program in the Division of Chemistry, a research team led by Professors Udo Schwarz and Eric Altman at Yale University is using a combination of scanning probe microscopy (SPM) methods and theory to obtain a detailed picture of the interaction between carbon monoxide (CO) and the single-molecule catalyst cobalt phthalocyanine (CoPc). The project will examine how new imaging capabilities can be used to probe the roles of surface interactions and of substituent groups on the CoPc catalysts in order to adjust the adsorption strength of CO, a key intermediate in the reduction and conversion of CO2 to methanol. This research is designed to address issues related to climate change by contributing to the creation of a reliable, carbon-neutral energy supply based on the catalytic conversion of CO2 into methanol. Methanol is a commodity chemical that can readily be stored and transported and either used as fuel directly or converted into other liquid fuels such as diesel, gasoline, or aviation kerosene. Recent work at Yale has identified immobilized CoPc molecules as a promising platform for promoting selective CO2 conversion to methanol, but little is known about how to optimize the activity, selectivity, and stability of this potential catalyst. Therefore, the research team is developing a chemical imaging approach to show how individual CoPc molecules interact with the supporting surface and with key intermediate species in the CO2 reduction process, including CO. The work has the potential to provide new methods for optimizing these interactions by tuning substituent groups on the CoPc catalyst. The detailed molecular-level understanding that emerges from this effort could lead to improvements in electrocatalytic performance. In addition to broader impacts related to the mitigation of climate change, the project will provide advanced student training opportunities in state-of-the-art imaging methods and supports outreach activities for the general public.The reduction of CO2 involves generating CO as an intermediate, therefore efficient methanol production requires that CO binding to the cobalt atom in CoPc is neither too strong nor too weak. Although CO binding can likely be fine-tuned by changing the catalyst structure, current spectroscopic methods are inadequate for understanding CO binding strength on a single-molecule basis. To alleviate this shortcoming, the research team uses advanced scanning probe microscopy methods to locally measure the CO adsorption strength as a function of catalyst structure and support, with the goal of enabling rational catalyst optimization. Key to the project are recent advances in SPM that provide the ability to image molecular structures, distinguish bond orders, and measure small distortions in molecular structures as electrons are injected into molecules using non-contact atomic force microscopy (NC-AFM) with CO-functionalized tips. For complementary information, results from NC-AFM imaging are combined with the measurement of local work function variations obtained by Kelvin probe microscopy and the electronic structure obtained through tunneling spectroscopy, which allow mapping of the positions of the highest occupied and lowest unoccupied molecular orbitals, total charge densities, and electron transfer to and from the support. As the third major element of this effort, scanning tunneling microscopy-based action spectroscopy should enable quantification on an individual molecule basis of how supports, adsorption sites and geometries, and substituent groups influence the adsorption of reactive intermediates in the conversion of CO2 to liquid fuelsThis 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.

在化学划分中的化学测量和成像（CMI）计划的支持下，由Udo Schwarz教授和耶鲁大学的Eric Altman领导的研究团队使用了扫描探针显微镜（SPM）方法和理论的组合，以获得碳二氧化碳（CO）和单人catical phthalt phthalt phthalt phthalt phthalt的详细图片。该项目将研究如何使用新的成像功能来探测表面相互作用和COPC催化剂上取代基团的作用，以调节CO的吸附强度，这是CO2降低和转化为甲醇的关键中间体。这项研究旨在通过基于二氧化碳转化为甲醇的催化转化来创建可靠的碳中性能源供应，以解决与气候变化有关的问题。甲醇是一种可以容易储存和运输的商品化学物质，可以直接用作燃料，或者转化为其他液体燃料，例如柴油，汽油或航空煤油。耶鲁大学最近的工作已将固定的COPC分子确定为促进选择性CO2转化为甲醇的有前途的平台，但是关于如何优化该潜在催化剂的活性，选择性和稳定性，知之甚少。因此，研究团队正在开发一种化学成像方法，以显示单个COPC分子如何与支撑表面相互作用以及在二氧化碳减少过程中与关键的中间物种相互作用，包括CO。这项工作有可能通过在COPC催化剂上调谐定产组来提供新方法来优化这些相互作用。从这项工作中得出的详细分子水平理解可能会改善电催化性能。除了与气候变化相关的更广泛的影响外，该项目还将在最先进的成像方法中提供高级学生培训机会，并为公众提供外展活动。CO2的降低涉及将CO作为中间体产生，因此有效的甲醇生产需要与COPC中的COPC cobalt Atom互动也不太强也不那么弱。尽管可以通过更改催化剂结构来微调CO结合，但是当前的光谱方法不足以理解单分子的CO结合强度。为了减轻这一缺点，研究团队使用先进的扫描探针显微镜方法来局部测量CO吸附强度，这是催化剂结构和支持的函数，目的是实现合理的催化剂优化。该项目的关键是SPM的最新进展，这些进步提供了对分子结构，区分键序的能力，并测量分子结构中的小变形，因为电子使用非接触式原子力显微镜（NC-AFM）注射到分子中，并用共官能化的技巧注入分子。为了获得互补信息，NC-AFM成像的结果与Kelvin Probe显微镜获得的局部工作功能变化相结合，以及通过隧道光谱获得的电子结构获得的电子结构，从而允许映射最高占据的最高且最低的无能力和最低无能力的分子轨道轨道轨道，总电荷密度，总电荷密度，以及电子辅助，以及来自电子的转换。作为这项努力的第三个主要要素，扫描基于隧道的动作光谱应在个人分子的基础上进行量化，即支持，吸附位点和几何形状和替代基团如何影响反应性中间体的吸附，从而通过co2授予的液体授予nsf的液体授予，并反映了NSF的液体基础，并反映了DEEM的授权，并以此为基础。和更广泛的影响审查标准。