One pot synthesis of hollow colloidal gel*

Liquid crystal (LC) phase transitions can drive the assembly of dispersed nanoparticles. Hollow microstructures of various morphologies can be created, on cooling through the nematic-isotropic transition temperature (T_NI) at different temperature quenches. At high quench rates single compartment hollow capsules are observed. These colloidal capsules frustrate orientational order in the liquid crystal leading to topological defects. These defects stabilize the capsules into a mechanically robust gel. The capsule sizes can be controlled by varying the quench depth. Here we present structural analysis using confocal and fluorescence imaging of these gels for a range of capsule sizes. We also observed continuous tubular network morphologies at lower quench rates. These networks under birefringence show the presence of defect lines and loops. Such one pot synthesis technique leads to the rapid self-assembly of liquid crystal nanocomposites, that may find applications in controlled release, sensing and catalysis.