Chemical Guidelines for Predictive Materials Integration in Hybrid Nanoparticles

Chemists draw diagrams that visually represent the application of important chemical and physical principles to a new idea or function, and then work to create the molecules and materials that make these designs a reality. For example, combining together catalysts and semiconductors at nanometer length scales can allow certain chemical reactions to occur when a light is turned on. While chemists can propose an almost limitless combination of materials that have potentially interesting and useful functions, it is not always easy to practically put together the materials in a way that enables these functions to be observed experimentally. Dr. Raymond Schaak, from the Pennsylvania State University University Park, is developing new capabilities for predictably combining materials and molecules at nanometer length scales. He is funded to identify new ways of creating interfaces between functional nanoscale materials using chemical reactions that couple together and transform nanoparticle building blocks. He is also studying important characteristics of these interfaces to better understand how targeted functions can be predictably achieved. Dr. Schaak is developing methods for depositing materials and molecules at precise locations on the surfaces of these coupled nanoparticle systems. The fundamental knowledge gained from this project helps to bridge the gap between what can be designed and what can be accessed experimentally for functional nanoscale materials of increasing chemical complexity. Dr. Schaak works on this research program with a diverse team of graduate and undergraduate students. He trains a diverse group of graduate and undergraduate students to develop, implement, and assess modular plug-and-play curricular materials (application-focused notes, case studies, collaborative problems, assessment tools) for contextualizing general chemistry units using cutting-edge research themes, impacting >2000 students initially plus many more through multiple

dissemination pipelines.

In this research program, Dr. Schaak of Pennsylvania State University is supported by the Macromolecluar, Supramolecular and Nanochemistry (MSN) Pprogram to develop new chemical strategies for constructing multi-component hybrid nanoparticles that integrate functional materials through well-defined interfaces at precise locations. A suite of nanoparticle heterocoupling, chemical transformation, and phase segregation reactions decouple two competing synthetic bottlenecks, functional materials incorporation and interface control, to generate new hybrid nanostructures. Microscopic and spectroscopic studies complement the synthetic efforts to provide new insights into interfacial composition, structure, and morphology. Additional efforts to control metal and ligand deposition at precise locations on the hybrid nanoparticle surfaces add additional interfaces and capabilities for directional surface interactions. These new chemical capabilities and insights are important for predictably synthesizing functional hybrid nanostructures of increasing chemical complexity across a wide range of applications. Because they incorporate nanoscale interfaces, colloidal hybrid nanoparticles serve as discrete model systems for larger multi-component architectures such as fuel cells, solar cells, and lab-on-a-chip devices. Dr. Schaak works on this research program with a diverse team of graduate and undergraduate students. He and his students also develop new teaching tools to provide application-focused context to topics in large introductory chemistry courses.

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.