Speaker: Shan Jiang, Ph.D., Associate Professor,

Department of Materials Science and Engineering, Iowa State University 

When symmetry is broken in anisotropic particles and molecules, new physics and structures emerge. Their interactions depend on directions, leading to intriguing assemblies and diffusion behaviors fundamentally different from conventional isotropic systems. A notable example is Janus particles, which act like small surfactant molecules, assembling into clusters and adsorbing strongly at interface. Exploiting these features, we discovered a unique self-stratification behavior driven by two orders of magnitude faster diffusion of Janus particles toward interface. The phenomenon is further harnessed to produce coating materials with novel layered structures with enhanced performance. Another example involves biobased polymers with distinctive conformations that modulate interactions with nanoparticles. By exploring the interplay between biobased polymers and nanoparticles, we demonstrated unconventional assemblies and developed materials with enhanced properties. These findings have established innovative platforms for material fabrication across diverse applications, including coatings and additive manufacturing.