Controlled Fabrication of Uniform Hollow Bowl-Shaped Microspheres Based on Polyphosphazene Material

Micro or nanoparticles with hollow interiors are receiving immense attention owing to their unique hollow structure and wide application potential. A novel hollow bowl-shaped microsphere based on a polyphosphazene material is successfully fabricated for the first time by a facile solvent-treatment process. Based on SEM and TEM observations, the obtained particle is proven to be uniform with a shell thickness of about 120 nm, and a tentative formation mechanism is suggested. By combination of the unique bowl-shaped structure, uniform microsize, and the superior properties of the hybrid polyphosphazene material, the products are envisioned to have promising applications in microreactors to fabricate functional composite particles, in catalysis, or the biomedical domain.