Date: 2 to 6 July, 2018

Rome, Italy

PhD-student of LNMM Alexander Omelyanchik took part on organization of the 25th International Symposium of Metastable, Amorphous and Nanostructured Materials (ISMANAM 2018) which was held from 2 to 6 July in Rome. As well he presented his work entitled “Magnetic properties of core/shell manganese oxide nanoparticles before and after degradation in water”.

Poster session:

In this work, magnetic properties of L-DOPA stabilized core/shell Mn3O4/MnO nanoparticles were investigated during the process of degradation [1-2]. The as prepared Mn3O4/MnO core/shell system demonstrates a low temperature magnetization reversal that is strongly affected by the presence of the MnO shell. As results, the finite coercivity slightly above the Curie temperature of the Mn3O4 phase, the horizontal displacement of the FC-hysteresis loop as well as the existence of a frustrated interfacial region determining the low temperature irreversibility were observed. On the other hand, the magnetic behavior of the aged system is dominated by the presence of Mn3O4 whose highly anisotropic character (i.e. high coercivity and high magnetization remanence) is attributed to the presence of a large fraction of surface spins. Such result is consistent with the structural evolution, from core/shell to hollow nanoparticles, as shown by TEM observation.

[1] B.H. McDonagh, G. Singh, S. Hak, S. Bandyopadhyay, I.L. Augestad, D. Peddis, et al., Small. 12, 301 (2016).
[2] A. Omelyanchik, G. Singh, B.H. McDonagh, V. Rodionova, D. Fiorani, D. Peddis, et al., Nanotechnology.
29(5), 055703 (2018).

A. Omelyanchik1, G. Singh2, B.H. McDonagh3, V. Rodionova1, D. Fiorani 4, D. Peddis 4, S. Lauretti 4

Center For Functionalized Magnetic Materials (FunMagMa), Immanuel Kant Baltic Federal University, Kaliningrad, 236041 Russia

Department of Materials Engineering, Norwegian University of Science and Technology (NTNU), 7491, Trondheim, Norway)

Ugelstad Laboratory, Dept. Of Chemical Engineering, Norwegian University of Science and Technology (NTNU)

Istituto di Struttura della Materia-CNR, 00015 Monterotondo Scalo (RM)

Correspondence to:

Immanuel Kant Baltic Federal University,

Gaidara 6, Kaliningrad, 236022, Russia