Magneto-ionic control of magnetism in two-oxide nanocomposite thin films comprising mesoporous cobalt ferrite conformally nanocoated with HfO2
Robbennolt, Shauna (Universitat Autònoma de Barcelona. Departament de Física)
Yu, Pengmei (Institut de Ciència de Materials de Barcelona)
Nicolenco, Aliona (Universitat Autònoma de Barcelona. Departament de Física)
Mercier Fernández, Pau (Universitat Autònoma de Barcelona. Departament de Física)
Coll, Mariona (Institut de Ciència de Materials de Barcelona)
Sort Viñas, Jordi (Universitat Autònoma de Barcelona. Departament de Física)

Date:	2020
Abstract:	Advances in nanotechnology require of robust methods to fabricate new types of nanostructured materials whose properties can be controlled at will using simple procedures. Nanoscale composites can benefit from actuation protocols that involve mutual interfacial interactions on the nanoscale. Herein, a method to create nanoscale composite thin films consisting of mesoporous cobalt ferrite (CFO) whose pore walls are nanocoated with HfO2 is presented. Porous CFO films are first prepared by sol-gel. Atomic layer deposition is subsequently used to conformally grow a HfO2 layer at the surface of the pore walls, throughout the thickness of the films. The magnetic properties of uncoated and HfO2-coated CFO mesoporous films are then modulated by applying external voltage, via magneto-ionic effects. The CFO-HfO2 composite films exhibit an enhanced magnetoelectric response. The magnetic moment at saturation of the composite increases 56% upon the application of −50 V (compared to 24% for CFO alone). Furthermore, dissimilar trends in coercivity are observed: after applying −50 V, the coercivity of the composite film increases by 69% while the coercivity of the CFO alone decreases by 25%. The effects can be reversed applying suitable positive voltages. This two-oxide nanocomposite material differs from archetypical magneto-ionic architectures, in which voltage-driven ion migration is induced between fully-metallic and oxide counterparts. The synthesized material is particularly appealing to develop new types of magnetoelectric devices with a highly tunable magnetic response.
Grants:	European Commission 648454 European Commission 875018 Agència de Gestió d'Ajuts Universitaris i de Recerca 2017/SGR-292 Agència de Gestió d'Ajuts Universitaris i de Recerca 2017/SGR-1519 Ministerio de Economía y Competitividad MAT2017-86357-C3-1-R Ministerio de Economía y Competitividad MAT2017-83169-R
Rights:	Tots els drets reservats.
Language:	Anglès
Document:	Article ; recerca ; Versió acceptada per publicar
Published in:	Nanoscale, Vol. 12, Issue 10 (March 2020) , p. 5987-5994, ISSN 2040-3372

DOI: 10.1039/C9NR10868H

Postprint 9 p, 1.2 MB

The record appears in these collections:
Research literature > UAB research groups literature > Research Centres and Groups (research output) > Experimental sciences > Group of Smart Nanoengineered Materials, Nanomechanics and Nanomagnetism (Gnm3) > SPIN-PORICS
Articles > Research articles
Articles > Published articles