Preparation of Ni/PSt/TiO₂ multiply coated spheres responsive to electric and magnetic fields

The multiply coated Ni/PSt/TiO₂ spheres with uniform size, high refractive index and easily assembling property by electric and magnetic fields were prepared. The multilayer complex spheres consisted of a modified nickel colloidal sphere as the core, a polymer polystyrene coating, and an outermost coating of titania. The prepared Ni/PSt/TiO₂ multilayer composite spheres were characterized by FT-IR, XRD, TEM, etc. Also, the composite particles showed well responses to electric and magnetic fields which were reflected by the formation of network structure under electric and magnetic fields superimposed in the perpendicular.