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The unique three-dimensional pore structure of KCC-1 has attracted significant attention and has proven to be different compared to other conventional mesoporous silica such as the MCM-41 family, SBA-15, or even MSN nanoparticles. In this research, we carefully examine the morphology of KCC-1 to define more appropriate nomenclature. We also propose a formation mechanism of KCC-1 based on our experimental evidence. Herein, the KCC-1 morphology was interpreted mainly on the basis of compiling all observation and information taken from SEM and TEM images. Further analysis on TEM images was carried out. The gray value intensity profile was derived from TEM images in order to determine the specific pattern of this unique morphology that is found to be clearly different from that of other types of porous spherical-like morphologies. On the basis of these results, the KCC-1 morphology would be more appropriately reclassified as bicontinuous concentric lamellar morphology. Some physical characteristics such as the origin of emulsion, electrical conductivity, and the local structure of water molecules in the KCC-1 emulsion were disclosed to reveal the formation mechanism of KCC-1. The origin of the KCC-1 emulsion was characterized by the observation of the Tyndall effect, conductometry to determine the critical micelle concentration, and Raman spectroscopy. In addition, the morphological evolution study during KCC-1 synthesis completes the portrait of the formation of mesoporous silica KCC-1.

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.

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