Controlled growth of Ni/NiO core–shell nanoparticles: Structure, morphology and tuning of magnetic properties
| Autor: | Sergio D'Addato, Paola Luches, Vincenzo Grillo, Alessandro Ponti, Maria Chiara Spadaro, Stefano Frabboni, Elena Capetti, Anna M. Ferretti, Sergio Valeri |
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| Jazyk: | angličtina |
| Rok vydání: | 2014 |
| Předmět: |
Ni
Materials science Scanning electron microscope Nickel oxide Non-blocking I/O Analytical chemistry Oxide General Physics and Astronomy Nanotechnology Surfaces and Interfaces General Chemistry Condensed Matter Physics Dark field microscopy Surfaces Coatings and Films NiO Magnetization chemistry.chemical_compound Gas-phase synthesis X-ray photoelectron spectroscopy chemistry Core-shell nanoparticles Scanning transmission electron microscopy Nickel Nickel Oxide core-shell nanoparticle magnetic proterties TEM SQUID Exchange bias |
| Zdroj: | Applied surface science 306 (2014): 2–6. doi:10.1016/j.apsusc.2014.02.060 info:cnr-pdr/source/autori:D'Addato, S.; Spadaro, M. C.; Luches, P.; Grillo, V.; Frabboni, S.; Valeri, S.; Ferretti, A. M.; Capetti, E.; Ponti, A./titolo:Controlled growth of Ni%2FNiO core-shell nanoparticles: Structure, morphology and tuning of magnetic properties/doi:10.1016%2Fj.apsusc.2014.02.060/rivista:Applied surface science/anno:2014/pagina_da:2/pagina_a:6/intervallo_pagine:2–6/volume:306 |
| DOI: | 10.1016/j.apsusc.2014.02.060 |
| Popis: | We performed a detailed study of Ni/NiO core-shell nanoparticles (NP) obtained with a gas aggregation source. The NP oxide shells were produced by oxidizing the NP with different procedures: deposition in oxygen atmosphere, post-annealing in air, sequential deposition of (a) first NiO layer, (b) Ni NP and (c) third NiO Layer. X-ray photoelectron spectroscopy from Ni 2p core-level gave information about the chemical state of Ni in the core and in the oxide shell, while scanning electron microscopy was used for investigation of the NP morphology. High quality scanning transmission electron microscopy in high angle annular dark field mode data demonstrated core-shell structure also for NiO/Ni NP/NiO samples. Field-cooled/zero-field-cooled magnetization curves and field-cooled isothermal hysteresis cycles at T = 5K were recorded by a SQUID magnetometer. In this way, the relation between magnetic properties and oxide shell structure was assessed, showing the role played by the control of the formation of oxide on the exchange bias and interparticle magnetic interaction. (C) 2014 Elsevier B.V. All rights reserved. |
| Databáze: | OpenAIRE |
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