Synthesis and magnetic properties of Ni–BaTiO₃ nanocable arrays within ordered anodic alumina templates

Abstract

A reliable and flexible synthesis route was used for processing high density Ni-BaTiO 3 nanocable arrays based on wet chemical impregnation and subsequent electrodeposition within a highly ordered unidirectional porous alumina membrane. The core-shell structure was carefully investigated by bright field scanning transmission electronic microscopy coupled with energy dispersive X-ray spectroscopy. The strength of the dipolar interaction arising from the packing density of the magnetic nanowires was correlated with the BaTiO 3 wall thickness through magnetometry and ferromagnetic resonance measurements. Our approach opens a pathway to obtain optimized nanostructured multiferroic composites exhibiting tunable magnetic properties.

Innovative architectures in ferroelectric multi-materials: Chemistry, interfaces and strain

“…We have combined electrochemical deposition and wet chemical impregnation processes within a highly ordered unidirectional porous alumina (AAO) membranes. 37 Core-shell multiferroic nanocables, that are very difficult to obtain using conventional lithographic techniques, are elaborated with compositions, morphologies and geometrical parameters controlled to a large extent. Magnetoelectric coupling through mechanical coupling can be expected considering such arrays of vertically aligned core-shell nanocables having large interface area.…”

“…The strength of the magnetic dipolar interaction arising from the packing density of the magnetic nanowires was correlated to the BaTiO 3 wall thickness through magnetometry and ferromagnetic resonance measurements. 37 SFCD process was also used to functionalize BaTiO 3 nanoparticles with an amorphous Al 2 O 3 shell of few nanometers ( Fig. 1(c)).…”

Specific core-shell approaches and related properties in nanostructured ferroelectric ceramics

“…Due to their reliability, flexibility, and reproducibility, template-assisted synthesis attracts a significant interest to build well-ordered three-dimensional arrays of nanowires (NWs) with high aspect ratio and high surface areas [73][74][75]. In a previous work, we have reported the two-steps synthesis of BaTiO3-Ni (BTO-Ni) nanocable (NC) arrays within porous anodic aluminium oxide (AAO) templates [76]. The limitations inherent to a thermal treatment performed at high temperature were pointed out.…”

“…It was shown that the thermal annealing required for BTO crystallization can (i) affect the ferroelectric BTO shell microstructure through defects-driven surface rearrangement and diffusion inside the AAO pores, and (ii) induce the template curvature, hence hindering the subsequent Ni electrodeposition into the BTO-coated AAO pores. The strength of the dipolar interaction arising from the packing density of the magnetic nanowires was correlated to the BaTiO3 wall thickness through magnetometry and ferromagnetic resonance measurements [76]. Magnetic properties of such core-shell nanowires can be tuned by an appropriate choice of membrane, packing fraction, geometric parameters (i.e., core radius and shell thickness) and composition.…”

Unidirectional Magnetic Anisotropy in Dense Vertically-Standing Arrays of Passivated Nickel Nanotubes

“…Among the multitude of F materials available today, the systems based on nickel (Ni) have been intensively studied lately, due to its abundance in nature which makes this material a cheap environmentally-friendly candidate, with excellent catalytic properties and with great potential to be used in energy and data storage applications [35][36][37]. Moreover, if desired, Ni can be easily converted into nickel oxide (NiO) which is an AF material with Néel temperature of ∼525 K [38,39].…”