Polymer particles with controllable and complex structures for high immobilization of noble-metal nanoparticles

This work demonstrates the fabrication of cationic polymer particles with controllable and complex structures for the high immobilization of noble-metal nanoparticles (NPs). The fabrication involves the use of a cationic extra monomer to synthesize polystyrene (PS) solid spheres with cationic character, followed by their transformation into complex-structured particles via the phase separation route in a seeded dispersion polymerization. Control of the phase separation enables the formation of PS particles with cage- and bowl-like shapes as well as hollow structures. The large surface areas of the complex-structured particles, as theoretically calculated using simple models, and the electrostatic attraction between them and the negatively charged noble-metal NPs, as experimentally observed, allow the high immobilization of noble-metal NPs onto their surfaces.