Effects of silica coating on the magnetic properties of magnetite nanoparticles

被引：70

作者：

Diorato Teixeira de Mendonca, Estelle Silva ^{[1
]}

Britto de Faria, Anna Carolina ^{[1
]}

Loureiro Dias, Silvia Claudia ^{[1
]}

Aragon, Fermin F. H. ^{[2
]}

Mantilla, John C. ^{[2
]}

Coaquira, Jose A. H. ^{[2
]}

Dias, Jose Alves ^{[1
]}

机构：

[1] Univ Brasilia, Inst Quim, Lab Catalise, Campus Univ Darcy Ribeiro,Asa Norte, BR-70910900 Brasilia, DF, Brazil

[2] Univ Brasilia, Inst Fis, Campus Univ Darcy Ribeiro,Asa Norte, BR-70910900 Brasilia, DF, Brazil

来源：

SURFACES AND INTERFACES | 2019年 / 14卷

关键词：

Magnetic nanoparticle; Magnetite; Surface functionalization; Silica coated magnetite; Silica coated magnetic composite; Acidity of magnetic nanoparticles; CATALYTIC-ACTIVITY; SURFACE; NANOCOMPOSITES; MICROSPHERES; REMOVAL; SHELL; CORE;

D O I：

10.1016/j.surfin.2018.11.005

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：

Research on magnetic nanoparticles of magnetite (MNPs) has intensified because it can be coated with different materials leading to diverse properties. In this work, MNPs and silica coated MNPs were synthesized by coprecipitation of Fe(III) and Fe(II) precursors, different proportions of tetraethylorthosilicate (TEOS), and scales showing high reproducibility and proximity of crystalline domains. Spectra of FT-IR exhibited the formation of Si-OH-Fe bonds. TEM images revealed that most of the MNPs were spherical with a fair distribution of encapsulated nanoparticles. Magnetization increased as the amount of silica coating increases. Silica coating did not modify the shape and structure of the MNPs cylindrical mesoporous open in the extremities. Adsorption of pyridine on the MNPs demonstrated the presence of hydrogen bonding, Lewis and Bronsted sites. For MNPs coated with silica, there was a neutralization of the Bronsted leading to weaker Lewis (coordinatively unsaturated iron) and hydrogen bonding sites (silanol groups).

引用

页码：34 / 43

页数：10

共 36 条

[1] Spin-glass-like behavior of uncompensated surface spins in NiO nanoparticulated powder [J].

Aragon, F. H. ;

de Souza, P. E. N. ;

Coaquira, J. A. H. ;

Hidalgo, P. ;

Gouvea, D. .

PHYSICA B-CONDENSED MATTER, 2012, 407 (13) :2601-2605

[2] Chemical and thermal stability of core-shelled magnetite nanoparticles and solid silica [J].

Cendrowski, Krzysztof ;

Sikora, Pawel ;

Zielinska, Beata ;

Horszczaruk, Elzbieta ;

Mijowska, Ewa .

APPLIED SURFACE SCIENCE, 2017, 407 :391-397

[3] Incorporation of luminescent nanocrystals into monodisperse core-shell silica microspheres [J].

Chan, Y ;

Zimmer, JP ;

Stroh, M ;

Steckel, JS ;

Jain, RK ;

Bawendi, MG .

ADVANCED MATERIALS, 2004, 16 (23-24) :2092-+

[4]

Cornell R M., 2007, The iron oxides, Structure, Properties, Reactions, Occurrences and Uses, VSecond

[5] Acidity and Characterization of 12-Tungstophosphoric Acid Supported on Silica-Alumina [J].

de Mattos, Flavia C. G. ;

de Carvalho, Eduardo N. C. B. ;

de Freitas, Elon F. ;

Paiva, Mateus F. ;

Ghesti, Grace F. ;

de Macedo, Julio L. ;

Dias, Silvia C. L. ;

Dias, Jose A. .

JOURNAL OF THE BRAZILIAN CHEMICAL SOCIETY, 2017, 28 (02) :336-+

[6] Superparamagnetic high-magnetization microspheres with an Fe3O4@SiO2 core and perpendicularly aligned mesoporous SiO2 shell for removal of microcystins [J].

Deng, Yonghui ;

Qi, Dawei ;

Deng, Chunhui ;

Zhang, Xiangmin ;

Zhao, Dongyuan .

JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 2008, 130 (01) :28-+

[7] Versatile heavy metals removal via magnetic mesoporous nanocontainers [J].

Dib, S. ;

Boufatit, M. ;

Chelouaou, S. ;

Sadi-Hassaine, F. ;

Croissant, J. ;

Long, J. ;

Raehm, L. ;

Charnay, C. ;

Durand, J. -O. .

RSC ADVANCES, 2014, 4 (47) :24838-24841

[8] Fe3O4@SiO2 Core/Shell Nanoparticles: The Silica Coating Regulations with a Single Core for Different Core Sizes and Shell Thicknesses [J].

Ding, H. L. ;

Zhang, Y. X. ;

Wang, S. ;

Xu, J. M. ;

Xu, S. C. ;

Li, G. H. .

CHEMISTRY OF MATERIALS, 2012, 24 (23) :4572-4580

[9] Calorimetric and spectroscopic investigation of the acidity of HZSM-5 [J].

Drago, RS ;

Dias, SC ;

Torrealba, M ;

deLima, L .

JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1997, 119 (19) :4444-4452

[10] Reducing Size-Dispersion in One-Pot Aqueous Synthesis of Maghemite Nanoparticles [J].

Drummond, A. L. ;

Feitoza, N. C. ;

Duarte, G. C. ;

Sales, M. J. A. ;

Silva, L. P. ;

Chaker, J. A. ;

Bakuzis, A. F. ;

Sousa, M. H. .

JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY, 2012, 12 (10) :8061-8066

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