|17-015||Go Kawamura||Kawamura, G.(Toyohashi University of Technology); Matsuda, A.(Toyohashi University of Technology); Boccaccini, A.R.(Instituto de Biomaterrales - Frederick Alexander University);||
Multiferroics, which exhibits strong magneto-electric effect, is attracting much attention due to its possibility of application to novel transducer, memory device, etc. A heterostructure consisting of nano-pillars of a ferromagnetic phase embedded in a ferroelectric matrix has previously been reported as one of the ideal nanocomposites showing noteworthy multiferroic properties. However, the complicated preparation process using extraordinary expensive equipment suppresses an expansion of research field. In this work, we selected BaTiO3 (BTO) and CoFe2O4 (CFO) as ferroelectric and ferromagnetic materials, respectively, and the pillar-matrix nanocomposites were fabricated by combination of conventional liquid-phase processes such as anodization, hydrothermal treatment, templating, co-precipitation, sol-gel, and electromagnetophoretic deposition (EMPD). For example, BTO nanotube arrays (NTAs) were fabricated by firstly anodizing Ti foil to obtain TiO2 NTAs, then hydrothermal treatment of TiO2 NTAs with Ba containing aqueous solution to convert TiO2 to BTO. On the other hand, BTO NTAs were also prepared by a sol-gel spin coating with an anodic aluminum oxide template. The tubular pores of BTO NTAs were filled with CFO via vacuum impregnation of CFO sol and/or EMPD of CFO nanoparticles, which were prepared by coprecipitation. The deposition of CFO on the inside of BTO NTAs was confirmed by electron microscopy and elemental distribution analysis. The magnetic, electric, and multiferroic properties were evaluated and discussed based on the structural differences among the samples.