Seminars

RSVP

Printing technologies have the potential to revolutionize manufacturing of electronic and energy materials by drastically reducing the energy cost while increasing throughput and agility. At the same time, additive manufacturing of such functional materials brings a new set of challenges demanding exquisite control over hierarchical structures down to the molecular-scale. During printing, the molecular assembly process strongly couples with multiphase interfaces and fluid flow, giving rise to intriguing far-from-equilibrium phenomena and offering opportunities to direct assembly by designing non-equilibrium drive forces. Inspired by biomolecular templates capable of surface reconfiguration, we developed a new concept of dynamic templating to direct assembly of -conjugated semiconducting polymers across length scales during solution printing. We showed that surface reconfigurability of dynamic templates enables cooperative multivalent interactions with the assembling media to attain a level of morphology control beyond that achieved using rigid (static) templates. Besides interface-directed assembly, we are keenly interested in flow-driven polymer assembly central to all printing processes. Integrating in situ imaging, scattering, spectroscopic experiments with finite element simulations, we discovered that printing flow can drastically alter chiral-liquid-crystal-mediated assembly pathways of conjugated polymers as to largely modulate charge transport and optoelectronic properties. The ability to control non-equilibrium assembly during printing sets the stage for dynamically modulating assembled structures on the fly. We demonstrated this concept by programming nanoscale morphology and structure color of bottlebrush block copolymers during 3D printing. In sum, our directed assembly approaches add a new dimension to additive manufacturing, enabling us to print functional polymers with precise multiscale structure and even programmable properties.

Ying Diao is an Associate Professor, I. C. Gunsalus Scholar, Dow Chemical Company Faculty Scholar, Lincoln Excellence for Assistant Professor (LEAP) Scholar at University of Illinois at Urbana-Champaign. She received her Ph.D. degree in Chemical Engineering from MIT in 2012. Her doctoral thesis was on understanding heterogeneous nucleation of pharmaceuticals by designing polymeric substrates. In her subsequent postdoctoral training at Stanford University, she pursued research in the thriving field of printed electronics. Diao group, started in 2015 at Illinois, focuses on understanding assembly of organic functional materials and innovating printing approaches that enable structural control down to the molecular and nanoscale. Her work has been frequently featured in scientific journals and news media such as the Science Magazine and Nature Materials. She is named to the MIT Technology Review’s annual list of Innovators Under 35 as a pioneer in nanotechnology and materials. She is also a recipient of NSF CAREER Award, NASA Early Career Faculty Award, 3M Non-Tenured Faculty Award and was selected as a Sloan Research Fellow in Chemistry as one of the “very best scientific minds working today”.

Diao Research Group