Preparation of raspberry-like ZIF-8/PS composite spheres via dispersion polymerization

Raspberry-like ZIF-8/PS composite spheres are prepared via dispersion polymerization of styrene with ZIF-8 and PVP as co-stabilizers. PVP is found to be crucial in determining morphology of the final product. It helps adherence of ZIF-8 nanoparticles to PS spheres. It is found that ZIF-8 nanoparticles thus prepared are partially embedded into PS sphere surfaces, resulting in a stable raspberry-like structure. Surface coverage of ZIF-8 can reach up to ∼32%. The effects of ZIF-8 content and PVP concentration on the particle size and morphology are examined in detail with the mechanisms elucidated. The raspberry-like spheres can be used as a template to grow thick ZIF-8 layers on the PS spheres through subsequent solvothermal treatment, leading to the formation of polymer-core MOF-shell structure.