Synthesis of BaTiO₃@TiO₂-sheet Core-Shell Structured Nanocomposites

Abstract

Core-shell structure nanocomposites have been of interest, as they can exhibit unique properties arising from the combination of peculiar characteristics of each component. In this research, core-shell structured nanocomposites, comprising barium titanate (BaTiO₃; BT) nanoparticles as the core and titanate (TiO₂) nanosheets as the shell, were prepared. The surface of barium titanate (BT) nanoparticles was modified chemically by hydrogen peroxide (H₂O₂) to create hydroxyl groups. TiO₂ nanosheets were deposited on the surface of the functionalized BT core, via alternate adsorption with oppositely charged polyelectrolyte poly(diallyl dimethylammonium) (PDDA) cations to produce an ultrathin TiO₂ shell layer that encapsulates BaTiO₃ nanoparticles. The structure of the core-shell particles was investigated in order to illustrate their formation mechanisms. Furthermore, this work reported the advance in utilizing a core-shell nanostructure to enhance relative permittivity and maintaining a low loss of polymer nanocomposites. A significant improvement in relative permittivity is attributed to the TiO₂ shell, which acts as polarizable dipoles and consequently enhances interfacial polarization. The results indicated that the structure of core-shell nanocomposites is attractive as a novel structural building block for fabricating novel materials and electronic devices.

Keywords:

• Barium titanate
• Titanate nanosheets
• Core-shell structure
• Nanocomposites

Additional information

Funding

This research was supported by King Mongkut’s Institute of Technology Ladkrabang under grant number KREF145908 and 2561-01-05-77.