Ferroelectric Hollow Particles Obtained by Solid-State Reaction

Maria Teresa Buscaglia, Vincenzo Buscaglia, Massimo Viviani, Giovanni Dondero, Serge Röhrig, Andreas Rüdiger, Paolo Nanni

Nanotechnology. 2008 Jun 4;19(22):225602.

PMID: 21825762

Abstract:

Hollow particles of barium titanate were obtained by a two-step process combining colloidal chemistry and solid-state reaction. BaCO(3) crystals (size ≈1 µm) suspended in a peroxy-Ti(IV) aqueous solution were coated with an amorphous TiO(2) shell using a precipitation process. Calcination of the BaCO(3)@TiO(2) core-shell particles at 700 °C resulted in the formation of BaTiO(3) hollow particles (shell thickness of ≈70 nm) which retain the morphology of the BaCO(3) crystals. Formation of the cavity occurs because out-diffusion of the core phase is much faster than in-diffusion of the shell material. X-ray diffraction (XRD) and Raman spectroscopy indicate that the hollow particles possess a tetragonal ferroelectric structure with axial ratio c/a = 1.005. Piezoresponse force microscopy has shown strong piezoactivity and 180° ferroelectric domains. The process described provides a general route to fabricate hollow ferroelectric structures of several compounds.

Chemicals Related in the Paper:

Catalog Number	Product Name	Structure	CAS Number	Price
AP12047277	Barium titanate(IV)		12047-27-7	Price