Surface and interface interplay on the oxidizing temperature of iron oxide and Au-iron oxide core-shell nanoparticles

Authors
Sarveena; Muraca, Diego; Mendoza Zélis, Pedro; Javed, Y.; Ahmad, N.; Vargas, Jose Marcelo; Moscoso Londoño, O.; Knobel, M.; Singh, M.; Sharma, S.K.
Publication Year
2016
Language
English
Format
article
Status
Published version
Description
This article presents the effect of oxidation temperature on shape anisotropy, phase purity and growth of core-shell heterostructures and consequently their effect on structure-property relationships. Iron oxide and Au-iron oxide nanocomposites were synthesized by a thermal decomposition method by passing pure oxygen at different temperatures (125-250 °C). The prepared nanoparticles were surface functionalized by organic molecules; the presence of the organic canopy prevented both direct particle contact as well as further oxidation, resulting in the stability of the nanoparticles. We have observed a systematic improvement in the core and shell shape through tuning the reaction time as well as the oxidizing temperatures. Spherical and spherical triangular shaped core-shell structures have been obtained at an optimum oxidation temperature of 125 °C and 150 °C for 30 minutes. However, further increase in the temperature as well as oxidation time results in core-shell structure amendment and results in fully grown core-shell heterostructures. As stability and ageing issues limit the use of nanoparticles in applications, to ensure the stability of the prepared iron oxide nanoparticles we performed XRD analysis after more than a year and they remained intact showing no ageing effect. Specific absorption rate values useful for magnetic fluid hyperthermia were obtained for two samples on the basis of detailed characterization using X-ray diffraction, high-resolution transmission electron microscopy, Mössbauer spectroscopy, and dc-magnetization experiments.
Fil: Sarveena. Himachal Pradesh University; India
Fil: Muraca, Diego. Universidade Estadual de Campinas; Brasil. Universidade Federal Do Abc;
Fil: Mendoza Zélis, Pedro. Instituto de Física la Plata (conicet- Universidad Nacional de la Plata); Argentina
Fil: Javed, Y.. University Of Agriculture, Faisalabad; Pakistán
Fil: Ahmad, N.. Université Paris Diderot - Paris 7; Francia
Fil: Vargas, Jose Marcelo. Comisión Nacional de Energía Atómica. Gerencia del Área de Energía Nuclear. Instituto Balseiro; Argentina
Fil: Moscoso Londoño, O.. Universidade Estadual de Campinas; Brasil
Fil: Knobel, M.. Universidade Estadual de Campinas; Brasil. Centro Nacional de Pesquisa Em Energia E Materiais;
Fil: Singh, M.. Himachal Pradesh University; India
Fil: Sharma, S.K.. Universidade Federal Do Maranhao; . Himachal Pradesh University; India
Subject
MULTIFUNCTIONAL NANOPARTICLES
IRON-OXIDE
MAGNETISM
SUPERPARAMAGNETISM
Nano-materiales
Nanotecnología
INGENIERÍAS Y TECNOLOGÍAS
Access level
Open access
License
https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
Repository
CONICET Digital (CONICET)
Institution
Consejo Nacional de Investigaciones Científicas y Técnicas
OAI Identifier
oai:ri.conicet.gov.ar:11336/70904