Effect of morphology and ageing on the magnetic properties of nickel nanowires

• Published in: Materials research bulletin 2019-12, Vol.120, p.110576, Article 110576
• Main Authors: Revathy, Ramany, Varma, Manoj Raama, Surendran, Kuzhichalil Peethambharan
• Format: Article
• Language: English
• Subjects: Ageing study; Effect of pH; Exchange bias; Hierarchical nickel nanowire; X- ray photoelectron spectroscopy
• ISSN: 0025-5408; 1873-4227
• DOI: 10.1016/j.materresbull.2019.110576

[Display omitted] •Ageing characteristics of chemically synthesized 1D Ni nanostructures are investigated.•Morphology and magnetic properties of Ni nanowires are dictated by the reaction pH.•Surface oxidation deteriorates the magnetic properties of hierarchical Ni nanowires.•Observation of exchange bias confirms the presence of FM-AFM interface in aged Ni sanmples. The growth of low dimensional magnetic nanostructures can create exciting properties which show a significant difference when compared to their bulk counterparts. The present work reports the effect of temperature and ageing on the magnetic properties of Ni nanowires. The synthesis of polycrystalline Ni nanostructures with different controllable morphologies was accomplished by a facile wet-chemical reduction route, disregarding hydrothermal conditions, magnetic fields or templates. Reaction pH is found to be critical in determining the morphology. Magnetic dipolar interactions drive sea-urchin-like nanoparticles to self-assemble, forming hierarchical nanowire structures that are analogous to the stem of the Euphorbia plant. The impact of morphology and temperature change on the magnetic properties is deeply investigated. Finally, the effect of ageing up to twelve months on the chemically derived nickel nanowire’s magnetic properties are investigated.