(177d) Multiscale Self-Assembly of Chiromagnetic Supraparticles with Hierarchical Structures

Self-assembly of chiral inorganic nanoparticles has drawn intensive attention due to its bridge effect to link singleton to multiple and thus generate chiral supraparticles (SPs) with diversified structures, which demonstrates plenty of potential applications in practical fields. Inspired by paramagnetic cobalt oxide (Co₃O₄) with strong chiroptical activity, we developed a method to synthesize various Co-based supraparticles by adjusting the initial conditions, such as reaction time, pH, and temperature. These supraparticles not only exhibit fancy hierarchical structures but also show significant chiromagnetic signals in visible wavelength range. Moreover, the chiromagnetic signals can be modulated by applying external magnetic field, which make it possible for us to endow various device with tunable chiromagnetic properties. As a demonstration, we also synthesized PAAM-SPs composite hydrogel with analogous chiroptical behaviors to show its anticipated practical capacity for further chiroptical devices.