Magnetically Responsive Photonic Crystal Microcapsules with Multi-model and Dynamic Color Change
摘要
Magnetically responsive photonic crystal (MRPC) liquid exhibits fast magnetic responsiveness and dynamic color variation, but its fluidity limits practical applications. To overcome this challenge, Fe3O4@PVP MRPC is utilized to develop MRPC microcapsules with a polydimethylsiloxane (PDMS) shell via droplet microfluidics. These microcapsules integrate excellent magnetochromism and durability. The microcapsules display fast magnetic response (<1 s) and wide spectral tunability (485–640 nm), allowing a broad color-tuning range from blue to red under magnetic fields. Notably, the MRPC microcapsules demonstrate long-term stability for over 100 days in polar solvents and epoxy resin. Additionally, MRPC microcapsule-based patterns can achieve dynamic color displays by varying the magnetic field strength, viewing angle, and magnet shape, respectively. Due to their unique multimodal and dynamic color changing properties, MRPC microcapsules show significant potential in the anti-counterfeiting field.