Abstract: The rapid development of nanofabrication technologies has led to the invention of nanoscale “smart” systems. There is a growing demand in achieving multifunctionality and anisotropy in these systems, where multiple components are precisely shaped and positioned into a single unit, such that they can realize unique magnetic, optical, and mechanical functions not found in a single-phase material. In this talk, I will address these challenges by exploiting solution-processed nanocrystal assemblies as new building blocks, to develop nanoscale
I will introduce the idea of colloidal nanocrystals, how they can be integrated into devices, and why they can realize key functionalities not accessible in conventional devices. This argument is further evidenced in two examples. First, I will present a “smart” window, whose light interaction can be reconfigurably modulated to actively control indoor light and heat. This window is fabricated by templated co-assembly of plasmonic and magnetic nanocrystals into nanorods. These magnetically switchable plasmonic nanorods can be actuated to either pass or block incident light under external magnetic field. Second, I will discuss the design rules for building 3-D nanorobots, which can potentially be used for in vivo cell manipulation. These 3-D nanostructures are achieved through the chemo-mechanical shape transformation of nanocrystal assemblies, leading to self-folding of a nanocrystal/bulk bilayer planar structure into a 3-D configuration.