Surface Charge and Coating of CoFe2O4 Nanoparticles: Evidence of Preserved Magnetic and Electronic Properties

被引：93

作者：

Nappini, Silvia ^{[1
]}

Magnano, Elena ^{[1
]}

Bondino, Federica ^{[1
]}

Pis, Igor ^{[1
,2
]}

Barla, Alessandro ^{[3
]}

Fantechi, Elvira ^{[4
]}

Pineider, Francesco ^{[4
]}

Sangregorio, Claudio ^{[5
]}

Vaccari, Lisa ^{[2
]}

Venturelli, Leonardo ^{[1
]}

Baglioni, Piero ^{[6
]}

机构：

[1] CNR, IOM, Lab TASC, I-34149 Trieste, Italy

[2] Elettra Sincrotrone Trieste SCpA, I-34149 Trieste, Italy

[3] CNR, ISM, Ist Struttura Mat, I-34149 Trieste, Italy

[4] INSTM, Dept Chem, I-50019 Florence, Italy

[5] CNR, INSTM, ICCOM, I-50019 Florence, Italy

[6] CSGI, Dept Chem, I-50019 Florence, Italy

来源：

JOURNAL OF PHYSICAL CHEMISTRY C | 2015年 / 119卷 / 45期

关键词：

IRON-OXIDE NANOPARTICLES; RAY CIRCULAR-DICHROISM; FERRITE NANOPARTICLES; ACID ADSORPTION; COBALT; STABILIZATION; FLUORESCENCE; FE; PHOTOELECTRON; CONTRAST;

D O I：

10.1021/acs.jpcc.5b04910

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

Magnetic nanoparticles (MNPs) have shown exceptional potential for several biological and clinical applications. However, MNPs must be coated by a biocompatible shell for such applications. The aim of this study is to understand if and how the surface charge and coating can affect the electronic and magnetic properties of CoFe2O4 MNPs. The role of the surface on the total magnetic moment of MNPs is a controversial issue, and several effects can contribute to make it deviate from the bulk value, including the charge, the nature of the coating, and also the synthetic technique. Positively and negatively charged uncoated CoFe2O4 NPs as well as citrate-coated NPs were prepared by soft chemistry synthesis. The electronic properties and cationic distribution of CoFe2O4 NPs were probed by X-ray absorption spectroscopy (XAS), X-ray magnetic circular dichroism (XMCD), and X-ray photoemission spectroscopy (XPS) techniques and confirmed by theoretical simulations. The overall magnetic behavior and the hyperthermic properties were evaluated by magnetometry and calorimetric measurements, respectively. The results show that all of the investigated CoFe2O4 NPs have high magnetic anisotropy energy, and the surface charge and coating do not influence appreciably their electronic and magnetic properties. In addition, the citrate shell improves the stability of the NPs in aqueous environment, making CoFe2O4 NPs suitable for biomedical applications.

引用

页码：25529 / 25541

页数：13

共 78 条

[1]

[Anonymous], SURF INTERFACE ANAL

[2] Nature of the Chemical Bond of Aqueous Fe2+ Probed by Soft X-ray Spectroscopies and ab Initio Calculations [J].