MAE Seminar: Nano-Architected Materials from Colloidal Nanoparticles

Zoom link below
Wendy Gu

Assistant Professor
Mechanical Engineering
Stanford University

Zoom link: Meeting ID: 969 0286 2157

Abstract: Innovations in energy and transportation are critically dependent on the development of advanced materials that can withstand harsh environments and severe loading conditions while remaining lightweight. Colloidal metallic nanoparticles with tailored properties can be used as building blocks for these materials. I will first discuss the consolidation of metallic glass nanoparticles to form nanostructured, bulk metallic glasses in which nanoscale interfaces control failure. Next, I will describe the development of novel two-photon lithography resins that enable the nano 3D printing of nanocomposites and nanoporous glassy carbon with high strength and energy absorption per weight. Luminescent metallic nanoclusters with high two-photon absorption are used as efficient photoinitiators and inorganic precursors in these resins. Pillars, honeycombs and octet lattices are fabricated that exhibit material nonlinearities that lead to enhanced mechanical performance. Lastly, I will describe the use of two-photon lithography to fabricate anisotropic colloidal microparticles, such as tetrahedra and truncated tetrahedra. These particles are self-assembled into 2D and 3D space-filling arrays at a liquid-solid interface. Enthalpy and entropy are used to understand the self-assembly process, and we explore the possibility of forming micro-textured surfaces through this manufacturing route.

Bio: Wendy Gu has been an assistant professor of mechanical engineering at Stanford University since 2017. Before this, Gu received her M.S./Ph.D. from Caltech in 2014 and was a postdoc at UC Berkeley from 2015-2017. Her research focuses on developing lightweight architected materials, nanostructured metals and structural alloys with superior strength and toughness, including for hydrogen environments, high-pressure conditions and as optical sensors. Major techniques within the group include nano-mechanical testing and in-situ imaging using transmission and scanning electron microscopy, synchrotron X-ray diffraction and tomography, nano-synthesis and self-assembly, and 3D printing. Gu is the recipient of the DOE Early Career Award, the ARO Young Investigator Award, the ACS Petroleum Research Fund Doctoral New Investigator Award and the Hellman Scholar Award.