Generation of Single Cation Sites Supported on Oxides

在化学系化学催化项目的支持下，加州大学滨江分校的马修·康利博士正在研究使用设计的多相催化剂加速化学反应的方法。这些新的催化剂被设计成提供比传统方法更节能的反应条件。Conley教授和他的研究团队致力于开发专门的高表面积材料，这些材料可以与金属试剂反应，形成具有可理解结构和可调催化活性的表面支撑金属位点。这种灵活的系统将用于研究各种重要的过程，以产生对日常生活很重要的商品和特种化学品。康利博士将让莫雷诺谷高中的学生参与这项研究计划，以帮助培养对STEM学科的兴趣，并鼓励他们对STEM职业道路的兴趣。单原子催化剂（SAC）为多相催化提供了一种比贵金属纳米颗粒更原子有效的策略，其中只有表面原子暴露于试剂。SAC的产生涉及将非常少量的贵金属原子分散到氧化还原活性氧化物载体上。康利博士和他的研究团队正在开发一种新的方法来制备单阳离子位点催化剂（SCS），并研究这些新材料对精细和商品化学工业都很重要的转化的催化反应性。该团队将使用这种合成技术来获得高表面积的氧化物，这些氧化物支持非常强的硅基刘易斯酸作为目标SCS的前体。硅烷包覆的氧化物将在有机金属络合物中用金属-卤化物键处理，以在明确定义的配位环境中形成单阳离子位点（SCS）。这种方法被用来安装单一的过渡金属阳离子均匀分散在氧化物表面掺杂弱配位阴离子，是互补的已知方法，产生SAC。由于这种生成SCS的方法可以与各种有机金属试剂配对，因此Conley小组正在研究这些材料支持的一系列催化活性，包括烯烃聚合，氢化胺化和氢化硅烷化化学，以及甲烷的部分氧化。这些为多相催化开发SCS的努力也将为研究生、本科生和高中生的多样化群体提供强大的培训环境。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。

With the support of the Chemical Catalysis Program in the Division of Chemistry, Dr. Matthew Conley of the University of California – Riverside is studying ways to accelerate chemical reactions using designer heterogeneous catalysts. These new catalysts are engineered to provide more energy-efficient reaction conditions than traditional approaches. Professor Conley and his research team are invested in developing specialized high surface area materials that can react with metal reagents to form surface-supported metal sites with understandable structures and tunable catalytic activity. This flexible system will be employed to investigate a variety of important processes to generate commodity and specialty chemicals that are important to everyday life. Dr. Conley will be involving students from a Moreno Valley high school in this research program to help foster interest in STEM disciplines and encourage interest in STEM career paths. Single atom catalysts (SACs) provide a more atom-efficient strategy for heterogeneous catalysis than noble metal nanoparticles where only surface atoms are exposed to reagents. The generation of SACs involves the dispersion of very small quantities of noble metal atoms onto a redox active oxide support. Dr. Conley and his research team are developing a new approach to preparing single cation site catalysts (SCSs) and studying the catalytic reactivity of these new materials towards transformations that are important to both the fine and commodity chemical industries. The team will be using this synthetic technology to access high surface area oxides that support very strong silylium Lewis acids as precursors for the targeted SCSs. The silylium-coated oxides will be treated with metal-halide bonds in organometallic complexes to form single cation sites (SCSs) in well-defined coordination environments. This methodology is being used to install single transition metal cations uniformly dispersed on oxide surfaces doped with weakly coordinating anions and is complementary to known methods that generate SACs. Because this approach to generating SCSs can be paired with a variety of organometallic reagents, the Conley group is investigating a range of catalytic activity supported by these materials including olefin polymerization, hydroamination, and hydrosilylation chemistry, as well as the partial oxidation of methane. These efforts to develop SCSs for heterogeneous catalysis also will serve as a strong training environment for a diverse group of graduate, undergraduate, and high school students.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.