Formation of three-dimensional (3D) Self-Assembled Clusters of Anisotropic Janus Particles in Microgravity

Abstract

Abstract The self-assembly of colloidal particles enables the creation of complex materials with tailored properties. This process, particularly involving anisotropic particles, can lead to the formation of structurally unique and complex assemblies that are not achievable with isotropic particles. On Earth, gravitational forces limit the investigation of these particles’ intrinsic motion and interactions, posing significant challenges to comprehensively understanding the fundamental forces governing their interactions. To overcome these limitations, this study, in collaboration with NASA’s Glenn Research Center (GRC), employs the Light Microscopy Module (LMM) aboard the International Space Station (ISS) to observe the self-assembly phenomena of anisotropic particles under microgravity conditions. Our investigation shows that anisotropic Janus particles with their distinctive properties can spontaneously organize into ordered structures under microgravity. This directional interaction among anisotropic particles is expected to enable control over assembly processes, forming three-dimensional (3D) clustered structures that are unattainable on Earth. Thus, this study not only advances our understanding of particle self-assembly in microgravity but also opens new avenues for synthesizing materials with novel functionalities through the unique assembly of anisotropic colloids.