Multiferroics based on ferrite (magnetic)/barium titanate (ferroic) composites for novel application

Abstract

Nowadays, nanostructured ferroics and multiferroics stimulated a sharply increasing interest due to their significant technological promise in novel devices. Recent emergent routes to produce nanoferroics and multiferroics using complex experimental tools allowed the addressability of ultimate structures still preserving ferroic and magnetic character and to detect novel properties. Magnetic and ferroelectric order coexists in magnetoelectric multiferroics; however the simultaneous presence of electric and magnetic dipoles does not still guarantee their coupling. Therefore, finding new multiferroics at room temperature or new mechanisms for magnetoelectric coupling besides the classical ones is of highest interest to drive to "exotic properties". In spite of hundreds of publications focused to single multiferroic materials or composite multiferroic materials in the last years, it remains a highly controversial concerning its phase stability, intrinsic polarization and switching, ferroelectric and magnetoelectric properties and controlling charged defects. On the other side, the combination of dissimilar materials in ferroic-based oxide nanocomposites resulted in totally novel functionality. Accordingly, innovative synthesis and atomically-controlled growth to produce single-/multi-phase nanostructured ferroics and multiferroics with desired size, shapes, assembly, interfaces and connectivity, advanced characterization and multiscale modeling expertise are strongly needed. The main aim of this research is to synthesize and characterize multiferroic materials based on composite ferrites-barium titanates compositions. To achieve this objective the several approaches will be used such as: a) to process nckel ferrites based composition as antigferromagnetic component using auto-combustion method, b) to process barium titanate as ferroelectric component using auto-combustion or mechanochemical methods, c) to prepare multiferroic composite based on ferroelectric/ferromagnetic composition using classical (mechanical) processing or wet chemical processing , d) to characterize properties of nananostructured ferroelectric and antiferromagnetic powders and components , e) to characterize properties of multifferoic composites and f) to characterize ferroelectric and magnetic behavior of multiferroic composites. It is needful to point that application of the above mentioned methods will enable preparation of nanopowders with well sinterability. Stable nanostructured ferroelectric and ferromagnetic powders will be used for fabrication of functional multiferroic material with both properties such as ferroelectric and magnetic. (AU)