The assembly of nanoparticles into solid assembly structures (so called ‘particle solids’) plays a central role in the integration of nanoparticle systems into device architectures for applications ranging from photovoltaics to solid state lighting. A major barrier in the scalable production of self-assembled particle solid structures is the brittle nature of particle solids that promotes crack formation during the processing and integration of particle assemblies. The goal of this proposal is to test the hypothesis that the grafting of copolymer ligands that are designed to enable “lock-and-key” interactions provides a path towards particle solids with enhanced fracture resistance and ability to “self-heal” structural damage. The proposed research plan will elucidate the role of polymer ligand composition on the mechanical properties and recovery behavior of particle solids. This could contribute to the development of a new class of ligand-modified particle systems that enable particle solids with hitherto unattainable property combinations that can be processed through solventless fabrication strategies.
Students will work with pre-synthesized nanomaterial systems that have been modified using a recently developed copolymer platform that features “self-heal ability.” The objective is to process these nanomaterials into bulk material forms for systematic characterization using thermogravimetry, dynamic mechanical analysis, and nanoindentation. In collaboration with graduate students, electron imaging analysis will be performed. Structure and property data will be combined to develop a physical model to interpret the origin of self-healing properties in copolymer-modified nanomaterial hybrid materials. This research will provide new opportunities for the facile fabrication of polymer nanocomposites with prescribed microstructure and enhanced performance and support transformative technological innovations, for example, in the area of solid-state lighting and materials for flexible photovoltaics.