Controllable synthesis of hierarchical polysilsesquioxane surfaces: from spheres-on-sphere to bowls-on-sphere structure

摘要

Hierarchical structured materials represent an interesting platform for many potential applications such as separation, catalyst and drug delivery etc. However, controlled fabrication of this special structure still remains a big challenge. In the present work, a controllable sol-gel procedure was developed to precisely fabricate polysilsesquioxane particles with bowls-on-sphere structure from mixed organoalkoxysilane precursors with sodium ligninsulfonate as surfactant and polystyrene spheres as structure-directing agents. The morphology of the particles can be fine-tuned by judiciously adjusting the ratio of two silane precursors, amount of ammonia, surfactant content and polystyrene amount. The formation mechanism of spheres-on-sphere structured polysilsesquioxane particles was explored.