Generation of Single Cation Sites Supported on Oxides

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.