Frontiers in Nanotechnology Seminar Series Presents Hongyou Fan from Sandia National Laboratories

“Pressure-induced nanoparticle assembly”

Precise control of structural parameters through nanoscale engineering to improve optical and electronic properties of functional nanomaterials continuously remains an outstanding challenge. Previous nanoparticle synthesis and assembly work has been conducted largely through solution chemistry at ambient pressure. It relies on specific chemical or physical interactions such as van der Waals interactions, dipole-dipole interactions, chemical reactions, ligand-receptor interactions, etc. In this presentation, I will introduce a new pressure-induced assembly and fabrication method that uses mechanical compressive force applied to nanoparticles to induce structural phase transition and to consolidate new nanomaterials with precisely controlled structures and tunable properties.

A reversible change in their assemblies and properties can be achieved and demonstrated by manipulating nanoparticle coupling through external pressure instead of through solution chemistry. In addition, over a certain threshold, the external pressure will force these nanoparticles into contact, thereby allowing the formation and consolidation of one- to three-dimensional nanostructures.  Through pressure-induced nanoparticle assembly, materials engineering and synthesis become remarkably flexible without relying on the traditional crystallization process where atoms/ions are locked in a specific crystal structure.  Therefore, morphology or architecture can be readily tuned to produce desirable properties for practical applications. (SAND2024-00611O)

Sandia National Laboratories is a multimission laboratory managed and operated by National Technology and Engineering Solutions of Sandia, LLC., a wholly owned subsidiary of Honeywell International, Inc., for the U.S. Department of Energy’s National Nuclear Security Administration under contract DE-NA0003525.