TY - JOUR

T1 - Magnetic granulometry and Mössbauer spectroscopy of FemOn–SiO2 colloidal nanoparticles

AU - Сергиенко, Елена Сергеевна

AU - Харитонский, Петр Владимирович

AU - Костеров, Андрей Александрович

AU - Гареев, Камиль Газинурович

AU - Везо, Ольга Сергеевна

N1 - Funding Information: Investigations of physico-chemical and magnetic characteristics of colloidal particles were carried out using the equipment of resource centers “Geomodel”, “Innovative technologies of composite nanomaterials”, “Nanotechnologies”, “X-ray diffraction methods of research” and “Center for Diagnostics of Functional Materials for Medicine, Pharmacology and Nanoelectronics” of Scientific Park of St. Petersburg State University. This work was supported by the Russian Foundation for Basic Research , grants. No. 16-32-60010 and No. 18-05-00626.

PY - 2018/9/1

Y1 - 2018/9/1

N2 - The colloidal nanoparticles Fe mO n–SiO 2 have been obtained using the sol–gel method. Based on the data obtained with transmission electron microscopy and dynamic light scattering, a lognormal size distribution of nanoparticles with an average size of 20–30 nm have been constructed. The shape of Mössbauer spectra implies that they have the characteristic relaxation time of the order of 10 –9–10 –10 s that corresponds to the grain size of about 10 nm. X-ray diffractometry indicates that the crystalline phase of the particles is magnetite. Hysteresis loops have been traced with a vibration sample magnetometer and the demagnetization curve of anhysteretic remanent magnetization measured with a SQUID magnetometer. Theoretical analysis of magnetization data based on a model of magnetostatically interacting superparamagnetic nanoparticles confirms the presence of both separate superparamagnetic magnetite particles (less than 20 nm in size) and those organized into clusters with an average size of about 30 nm.

AB - The colloidal nanoparticles Fe mO n–SiO 2 have been obtained using the sol–gel method. Based on the data obtained with transmission electron microscopy and dynamic light scattering, a lognormal size distribution of nanoparticles with an average size of 20–30 nm have been constructed. The shape of Mössbauer spectra implies that they have the characteristic relaxation time of the order of 10 –9–10 –10 s that corresponds to the grain size of about 10 nm. X-ray diffractometry indicates that the crystalline phase of the particles is magnetite. Hysteresis loops have been traced with a vibration sample magnetometer and the demagnetization curve of anhysteretic remanent magnetization measured with a SQUID magnetometer. Theoretical analysis of magnetization data based on a model of magnetostatically interacting superparamagnetic nanoparticles confirms the presence of both separate superparamagnetic magnetite particles (less than 20 nm in size) and those organized into clusters with an average size of about 30 nm.

KW - Magnetic granulometry

KW - Magnetite

KW - Mössbauer spectroscopy

KW - Nanoparticles

KW - Silica

KW - Superparamagnetism

UR - http://www.scopus.com/inward/record.url?scp=85046083224&partnerID=8YFLogxK

U2 - 10.1016/j.jmmm.2018.04.044

DO - 10.1016/j.jmmm.2018.04.044

M3 - Article

VL - 461

SP - 30

EP - 36

JO - Journal of Magnetism and Magnetic Materials

JF - Journal of Magnetism and Magnetic Materials

SN - 0304-8853

IS - 1

ER -