title: Dielectric spectroscopy of nano BaTiO3 confined in MCM-41 mesoporous molecular sieve materials.
abstract: Dielectric properties of barium titanate (BaTiO3) particles, synthesized directly in the pores of MCM-41 materials, have been investigated in the frequency range from 20 Hz to 1 MHz for temperature intervals from 100 K to 500 K. The dielectric spectra of BaTiO3 confined in these molecular sieves were compared with the results obtained from the investigation of pure MCM-41 materials. Obtained results confirmed successful incorporation of BaTiO3 into porous matrix, but no phase transition from paraelectric to ferroelectric phase was observed due to the particle size being smaller than the critical size. Also, the overall dielectric response of investigated materials is strongly influenced by adsorbed water molecules.
authors.affiliation: Physic Faculty, Vilnius University, Sauletekio 9, Vilnius LT-10222, Lithuania. martynas.kinka@ff.vu.lt
authors.forename: Martynas
authors.initials: M
authors.lastname: Kinka
authors.forename: Juras
authors.initials: J
authors.lastname: Banys
authors.forename: Winfried
authors.initials: W
authors.lastname: Böhlmann
authors.forename: Eicke
authors.initials: E
authors.lastname: Bierwirth
authors.forename: Martin
authors.initials: M
authors.lastname: Hartmann
authors.forename: Dieter
authors.initials: D
authors.lastname: Michel
authors.forename: Georg
authors.initials: G
authors.lastname: Völkel
authors.forename: Andreas
authors.initials: A
authors.lastname: Pöppl
mesh_terms: D017609:Barium Compounds / Q000737:chemistry* / Q000528:radiation effects*; D017097:Electric Impedance; D004563:Electrochemistry / Q000295:instrumentation / Q000379:methods*; D004574:Electromagnetic Fields; D049329:Nanostructures / Q000737:chemistry* / Q000528:radiation effects / Q000648:ultrastructure*; D010316:Particle Size; D016062:Porosity; D013057:Spectrum Analysis; D014025:Titanium / Q000737:chemistry* / Q000528:radiation effects*
chemical_list: D017609:Barium Compounds; C024547:barium titanate(IV); D014025:Titanium