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New Strategies for Creating Single and Dual Atom Catalysts on Silica Surfaces

在二氧化硅表面制造单原子和双原子催化剂的新策略

基本信息

批准号：
1900100
负责人：
Janet Bluemel
金额：
$ 44.96万
依托单位：
Texas A&M University
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2019
资助国家：
美国
起止时间：
2019-08-15 至 2023-07-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1900100&HistoricalAwards=false
关键词：
New Strategies Creating Single Dual

项目摘要

Catalysts allow reactions to proceed faster and to produce greater quantities of desirable products. Industrial chemistry would not be possible without the use of catalysts. However, big challenges remain regarding the sustainable use and recycling of catalysts. An optimal catalyst would consist of only one or two atoms that are prevented from grouping together and forming large bundles (aggregates). This separation of atoms can be achieved by arranging the atoms on a surface and retaining them at their specific surface sites. In this project, Professor Janet Bluemel of Texas A&M University is making use of two earlier discoveries to reach this goal. First, a well-defined one layer (monolayer) of metal complexes are placed on surfaces such as silica. The metal complexes are then modified to form single atoms that remain in place, dispersed on the surface. Similarly, two-atom assemblies are being prepared from metal complexes containing two different metal centers that are bound to the surface. Professor Bluemel's group is exploring the catalytic activities of these single- and dual-atom catalysts, their ability to form products selectively, and their recyclability. Different analytical approaches are being used and refined to obtain better insight into the surface processes and ultimately generate more efficient catalysts with superior characteristics. The project is enhancing the fundamental knowledge about how to create well-defined, efficient, recyclable catalysts in general and is leading to more sustainable processes. This project also provides broad, in-depth training for undergraduate and graduate students in Professor Bluemel's laboratory. In particular, the students are provided with opportunities for direct interaction with both domestic and international chemical companies, thus giving them unique and beneficial industrial experience.With funding from the Chemical Catalysis Program of the Chemistry Division, Professor Janet Bluemel of Texas A&M University is investigating dynamic processes on silica surfaces that involve supported molecular nickel, palladium, and copper complexes. The species are supported by tethering the complexes to the surface with the use of linkers. The tethered species are used as precursors to deliberately create well-defined single- and dual metal atom catalysts on surfaces such as silica. Dynamic processes do not occur only when covalently immobilized catalysts are suspended in a solvent. The Bluemel group has discovered that metal complexes adsorbed via Van der Waals interactions also display different modes of mobility on surfaces within pores, even in the absence of a solvent. At present there is a rudimentary understanding of how catalysts and their precursors diffuse in suspension or on dry surfaces. The ultimate goal of this project is to exploit the impact of specific tridentate phosphine linkers and the dry adsorption of nickelocene, which leads to well-defined monolayers, and to explore new methods for generating single- and dual atom catalysts (SACs, DACs) and well-defined nanoparticles on oxide surfaces. All approaches, which aim at stabilizing the metal particles and preventing their unrestricted growth are only feasible on surfaces. Investigating molecular immobilized and adsorbed catalyst precursors and the supported active metal catalysts generated from them, improves the understanding of their decomposition, agglomeration, and formation of metal particles. Direct insight regarding the structure and dynamics of all surface species is provided by High Resolution Transmission Electron Microscopy, dia- and paramagnetic 1H, 2H, 13C, 29Si, and 31P Magic Angle Spinning Nuclear Magnetic Resonance Spectroscopy of the dry materials and other techniques.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.

催化剂使反应进行得更快，并产生更多的所需产品。没有催化剂，工业化学就不可能.然而，在催化剂的可持续利用和回收方面仍然存在巨大挑战。最佳的催化剂将仅由一个或两个原子组成，这些原子被阻止聚集在一起并形成大的束（聚集体）。这种原子的分离可以通过将原子排列在表面上并将它们保留在其特定的表面位置来实现。在这个项目中，德克萨斯A M大学的Janet Bluemel教授正在利用两个早期的发现来实现这一目标。首先，将明确定义的一层（单层）金属络合物放置在诸如二氧化硅的表面上。然后金属配合物被修饰以形成保留在原位、分散在表面上的单个原子。类似地，双原子组装体由含有两个不同金属中心的金属络合物制备，所述金属中心结合到表面。Bluemel教授的团队正在探索这些单原子和双原子催化剂的催化活性，它们选择性地形成产品的能力以及它们的可回收性。不同的分析方法正在使用和完善，以获得更好的洞察表面过程，并最终产生更有效的催化剂与上级的特点。该项目正在提高关于如何创造定义明确、高效、可回收的催化剂的基本知识，并导致更可持续的工艺。该项目还为Bluemel教授实验室的本科生和研究生提供了广泛，深入的培训。特别是，学生们有机会与国内外化学公司直接互动，从而为他们提供独特而有益的工业经验。在化学系化学催化项目的资助下，德克萨斯农工大学的Janet Bluemel教授正在研究二氧化硅表面上涉及负载分子镍、钯和铜配合物的动态过程。通过使用连接剂将复合物拴系到表面来支持这些物质。被束缚的物质被用作前体，以在诸如二氧化硅的表面上故意产生明确的单金属原子和双金属原子催化剂。动态过程并不只发生在共价固定的催化剂悬浮在溶剂中。Bluemel小组已经发现，即使在没有溶剂的情况下，通过货车德瓦尔斯相互作用吸附的金属络合物也在孔内的表面上显示出不同的迁移模式。目前，对催化剂及其前体在悬浮液中或干燥表面上的扩散有初步的了解。该项目的最终目标是利用特定的三齿膦连接体和二茂镍的干吸附的影响，从而产生明确的单分子层，并探索在氧化物表面产生单原子和双原子催化剂（SAC，DAC）和明确的纳米颗粒的新方法。所有旨在稳定金属颗粒并防止其无限制生长的方法仅在表面上可行。研究分子固定化和吸附的催化剂前体和由它们产生的负载型活性金属催化剂，提高了对它们的分解，团聚和金属颗粒形成的理解。通过高分辨率透射电子显微镜，对1H，2H，13C，29Si，和31 P魔角旋转核磁共振光谱的干材料和其他技术。这个奖项反映了NSF的法定使命，并已被认为是值得支持，通过评估使用基金会的智力价值，更广泛的影响审查标准。

项目成果

期刊论文数量（13）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Creating Solid Solutions of Metallocenes: Migration of Nickelocene into the Ferrocene Crystal Lattice in the Absence of a Solvent

创建茂金属固溶体：在没有溶剂的情况下茂镍迁移到二茂铁晶格中

DOI：
10.1021/acs.jpcc.2c07441
发表时间：
2023
期刊：
The Journal of Physical Chemistry C
影响因子：
0
作者：
Harmon-Welch, Gabrielle E.;Hoefler, John C.;Trujillo, Martha R.;Bhuvanesh, Nattamai;Bakhmutov, Vladimir I.;Blümel, Janet
通讯作者：
Blümel, Janet

Synthesis and characterization of tridentate phosphine ligands incorporating long methylene chains and ethoxysilane groups for immobilizing molecular rhodium catalysts

DOI：
10.1016/j.mcat.2019.110629
发表时间：
2019-12-01
期刊：
MOLECULAR CATALYSIS
影响因子：
4.6
作者：
Guenther, J.;Reibenspies, J.;Blumel, J.
通讯作者：
Blumel, J.

Molecular Dynamics and Surface Interactions of Nickelocene Adsorbed on Silica: A Paramagnetic Solid-State NMR Study

二氧化硅上吸附的茂镍的分子动力学和表面相互作用：顺磁固态核磁共振研究

DOI：
10.1021/acs.langmuir.2c00301
发表时间：
2022
期刊：
Langmuir
影响因子：
3.9
作者：
Benzie, Jordon W.;Harmon-Welch, Gabrielle E.;Hoefler, John C.;Bakhmutov, Vladimir I.;Blümel, Janet
通讯作者：
Blümel, Janet

Hydrogen peroxide adducts of triarylphosphine oxides