a b s t r a c tDoping of manganese (Mn 3 þ /Mn 4 þ ) into the Aurivillius phase Pb 1 À x Bi 4 þ x Ti 4 À x Mn x O 15 was carried out using the molten salt technique for various Mn concentrations (x ¼0, 0.2, 0.4, 0.6, 0.8, and 1). Single phase samples could be obtained in the composition range with x up to 0.6 as confirmed by X-ray and neutron diffraction analysis. Dielectric measurements show a peak at 801, 803, 813 and 850 K for samples with x ¼0, 0.2, 0.4, and 0.6, respectively, related to the ferroelectric transition temperature (T c ). The main contribution of the in-plane polarization for x r0.2 which was calculated from the atomic positions obtained by the structure analysis is the dipole moment in the Ti(1)O 6 layer; however, for x Z 0.4 the polarization originates from the dipole moment in the Ti(2)O 6 layer. Mn doping in the Pb 1 À x Bi 4 þ x Ti 4 À x Mn x O 15 does not show any long range magnetic ordering.

We report on electrical bias voltage manipulation of the magnetic domain structures of patterned ferromagnetic Fe dots on a ferroelectric BaTiO3 underlayer using a scanning probe microscope technique. Piezoresponse force microscopy is used to apply local electric field on the Fe dots/BaTiO3 hybrid structure and to map the ferroelectric domain structures simultaneously. Magnetic force microscope observation also demonstrates that the magnetic domain structures of the Fe dots significantly change with the application of voltage at room temperature through the coupling between piezoelectric and magnetostrictive effects, indicating that the Fe dots/BaTiO3 hybrid structure provides a promising basis for controlling micromagnetic domain structures using electric voltage.

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Apatite-type lanthanum silicates show a great potential to be used as an electrolyte for intermediate-to low-temperature (600-700 C) solid oxide fuel cells (ITSOFC). However, so far these materials need to be prepared using a very high-temperature method, thus there is a growing interest to prepare apatites at lower temperatures. This paper reports the synthesis of undoped La 9.33 Si 6 O 26 and doped apatites (La 9 CaSi 6 O 26,5 , La 9 SrSi 6 O 26,5 , and La 9 BaSi 6 O 26,5 ) from raw materials La 2 O 3 , Na 2 SiO 4 , BaCO 3 , CaCO 3 , and SrCO 3 using a hydrothermal method. The polycrystalline apatites were obtained as a white powder, after the basic solution of the reagent mixture was heated at 240 C in an autoclave for 3 days. Le Bail refinement of the X-ray powder diffraction data showed that the compounds have a hexagonal cell (P 6 3 /m space group). In this paper, the undoped La 9.33 Si 6 O 26 and La-doped apatite ionic conductivities are also presented.