NSF-DFG Confine: Building functional supraparticles through directed assembly of nonspherical nanoparticles under confinement

Indiana University, Bloomington IN

Investigators

Abstract

Nanoparticles are finding use in almost all sectors of our economy from personal care to drug delivery. Their utility arises from the ability to access new properties that depend on their size, shape, and precise arrangement – called self-assembly. Self-assembly of nanoparticles in confined geometries hold the promise to build functional materials and devices with important properties that are otherwise not available. This award is a collaboration between Indiana University in the United States and Friedrich-Alexander-Universität Erlangen-Nürnberg in Germany to create well-defined supraparticles consisting of tens to thousands of nonspherical nanoparticles through directed self-assembly within liquid droplets and small channels. This award will expand the toolbox of supraparticle-by-design and will lay the groundwork for future computational studies of nanoparticle assembly by incorporating realistic interactions. Broader impacts of this project emphasize collaboration between experimentalists and computational scientists to enhance graduate and undergraduate education through multidisciplinary research. Summer research opportunities will be provided to students from underrepresented groups. Interactive modules to illustrate basic concepts of self-assembly will be designed and presented at local science museums and festivals. The overall objective of this award is to advance the design and synthesis of supraparticles by leveraging confined geometries to control nanoparticle assembly. Three aims will be undertaken. First, experimental, and computational approaches for the assembly of nonspherical nanoparticles into discrete supraparticles using emulsion droplets as templates will be established. Second, emulsion droplets generated using conventional emulsification methods and microfluidics to achieve precision synthesis of supraparticles composed of non-centrosymmetric nanoparticles will be leveraged. Third, one-dimensional supraparticles with emergent chiral optical properties via crystallization under cylindrical confinement will be fabricated. The interplay between experiment, establishing improved synthesis and characterization protocols, and theory, advancing coarse-grained modeling and simulation algorithms, will improve the fundamental understanding of self-assembly pathways in spherical and cylindrical confinement. The findings obtained and insights gained will also have applications in other systems that are affected by geometric constraints, such as crystallization of water in pores, virus capsid formation, biomineralization, macromolecular organization, and molecular packing in cells. This project was awarded through the “Chemistry and Transport in Confined Spaces (NSF-DFG Confine)" opportunity, a collaborative solicitation that involves the National Science Foundation and Deutsche Forschungsgemeinschaft (DFG). 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.