High coercivity sized controlled cobalt-gold core-shell nano-crystals prepared by reverse microemulsion

被引：7

作者：

Bahmanrokh, Ghazaleh ^{[1
]}

Hashim, Mansor ^{[1
]}

Soltani, Nayereh ^{[2
]}

Ismail, Ismayadi ^{[1
]}

Vaziri, Parisa ^{[3
]}

Navaseri, Manizheh ^{[2
]}

Erfani, Maryam ^{[2
]}

Kanagesan, Samikannu ^{[1
]}

机构：

[1] Univ Putra Malaysia, Adv Mat & Nanotechnol Lab, Inst Adv Technol, Upm Serdang 43400, Selangor, Malaysia

[2] Univ Putra Malaysia, Dept Phys, Fac Sci, Upm Serdang 43400, Selangor, Malaysia

[3] Shahid Beheshti Univ Med Sci, Dept Med Phys & Biomed Engn, Tehran, Iran

来源：

MATERIALS RESEARCH BULLETIN | 2013年 / 48卷 / 10期

关键词：

Magnetic materials; Nanostructures; Chemical synthesis; Magnetic properties; X-ray diffraction; NANOPARTICLES; NANOCRYSTALS; LAYER; ZNS;

D O I：

10.1016/j.materresbull.2013.06.021

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

Size-controlled cobalt-gold core-shell nanoparticles were synthesized via the reverse-micelle microemulsion method. In order to control the size of the nanoparticles, the nucleation and growth process were performed within a confined space by adjusting the water to surfactant ratio of reverse micelles solution during synthesis. The crystallinity percentage and percentage of phases presented in Co-Au core-shell nanoparticles were calculated using X-ray diffraction data. The results from transmission electron microscopy provide direct evidence for core-shell structure nanomaterials. Magnetic properties of the samples were investigated using a vibrating sample magnetometer. The as-prepared samples showed significant coercivity at room temperature. The intrinsic blocking temperature was experimentally deduced from zero-field-cooled warmed (ZFC-W) curves by a simple method without employing an external magnetic field. The B-field dependence temperature data of Co-Au nanoparticles exhibited an intrinsic blocking temperature at 45 K. Annealing these samples at 400 degrees C caused an increase in particle size, crystallinity percentage and further enhanced their magnetic properties. (c) 2013 Elsevier Ltd. All rights reserved.

引用

页码：4039 / 4047

页数：9

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