Multifunctional nanostructured Co-doped ZnO: Co spatial distribution and correlated magnetic properties
Abstract: In this report we present a systematic structural and magnetic analysis of Co-doped ZnO nanoparticles prepared via a microwave-assisted hydrothermal route. The structural data confirm the incorporation of Co ions into the wurtzite ZnO lattice and a Co concentration mainly near/at the surface of the nanoparticles. This Co spatial distribution is set to passivate the surface of the ZnO nanoparticles, inhibiting the nanoparticle growth and suppressing the observation of a ferromagnetic phase. Based on experimental and theoretical results we propose a kinetic-thermodynamic model for the processes of nucleation and growth of the Co-doped ZnO nanoparticles, and attribute the observed ferromagnetic order to a ferromagnetism associated with specific defects and adsorbed elements at the surface of the nanoparticle. Our findings give valuable contribution to the understanding of both the doping process at the nanoscale and the nature of the magnetic properties of the Co-doped ZnO system.
Author(s): da Silva, RT; Mesquita, A; de Zevallos, AO; Chiaramonte, T; Gratens, X; Chitta, VA; Morbec, JM; Rahman, G; Garcia-Suarez, VM ; Doriguetto, AC; Bernardi, MIB; de Carvalho, HB.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
Volume: 20 Pages: 20257-20269 Published: AUG 14 2018
O Laboratório Aberto de Interatividade para Disseminação do Conhecimento Científico e Tecnológico (LAbI), vinculado à Universidade Federal de São Carlos (UFSCar), é voltado à prática da divulgação científica pautada na interatividade; nas relações entre Ciência, Arte e Tecnologia.
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