20 / 23
Page 92
conferenceseries
.com
Volume 6
Research & Reviews: Journal of Material Sciences
ISSN: 2321-6212
Magnetic Materials 2018
October 22-23, 2018
October 22-23, 2018 | Rome, Italy
3
rd
International Conference on
Magnetism and Magnetic Materials
Iron oxides/hydroxides magnetic biomaterials for application in electronics and medicine
Ivan Nedkov
Institute of Electronics, Bulgarian Academy of Sciences, Bulgaria
N
anosized biogenic iron oxides/hydroxides are promising alternatives for microetoelectronics. They have been used in
“
in vivo
” experiments in NMR, for better contrast. The recently developed biotechnology was focused on acquiring
new physical data for application in electronics and medicine of the biogenic material obtained due to the metabolism in
laboratory conditions of iron-oxidizing bacteria from the genus
Leptothrix.
Powders and coatings on glass samples were under
investigation. Analysis of the data collected show that the Fe
2+
depending from the growth media could transformed into Fe
3+
or Fe
2.5+
in the form of two types of oxides/(oxy)hydroxides such as lepidocrocite (
ɣ
-FeOOH) and magnetite (Fe
3
O
4
), all with
nanostructured morphology. The particle's size (below 30 nm) and crystalline structure of the bioproducts were investigated
by XRD, SEM, TEM, Mössbauer and Raman Spectroscopies. The structural deviations are observed in biogenic iron oxides/
hydroxides by comparison with the conventional materials. The results further demonstrate that lepidocrocite is the main
product of the bacteria’s metabolism, both in the film and in the sediment's powder. The formation of Fe
3
O
4
passes through
intermediate phase – "green rust" reaction and the quantity could be controlled during the preparation. The work report results
were based on SQUID measurements on the magnetic properties - M(T) of the biogenic ferroxides. Monodomain particles
which are antiferromagnetic -
ɣ
-FeOOH and ferrimagnetic - Fe
3
O
4
were received. For the needle like crystals of lepidocrocite
the outer casing deviations were observed which modified the magnetic properties about 50 K. The new biogenic materials
showed superparamagnetic behavior and high sensitivity to electromagnetic radiation. The biogenic tubular formation with a
single-phase iron oxides/hydroxides inclusions in biogenic matrix was also investigated. Contributions for understanding the
structural, magnetic and optical properties are important for fundamental research, but also some suggestions for potential
applications in electronics and information technologies are proposed.
nedkovivan@yahoo.co.ukRes. Rev. J Mat. Sci. 2018, Volume 6
DOI: 10.4172/2321-6212-C6-030