title: Interfacial strain and defects in asymmetric Fe-Mn oxide hybrid nanoparticles.
abstract: Asymmetric Fe-Mn oxide hybrid nanoparticles have been obtained by a seed-mediated thermal decomposition-based synthesis route. The use of benzyl ether as the solvent was found to promote the orientational growth of Mn1-xO onto the iron oxide nanocube seeds yielding mainly dimers and trimers whereas 1-octadecene yields large nanoparticles. HRTEM imaging and HAADF-STEM tomography performed on dimers show that the growth of Mn1-xO occurs preferentially along the edges of iron oxide nanocubes where both oxides share a common crystallographic orientation. Fourier filtering and geometric phase analysis of dimers reveal a lattice mismatch of 5% and a large interfacial strain together with a significant concentration of defects. The saturation magnetization is lower and the coercivity is higher for the Fe-Mn oxide hybrid nanoparticles compared to the iron oxide nanocube seeds.
authors.affiliation: Arrhenius Laboratory, Department of Materials and Environmental Chemistry, Stockholm University, Stockholm, Sweden. lennart.bergstrom@mmk.su.se.
authors.forename: Arnaud
authors.initials: A
authors.lastname: Mayence
authors.forename: Madeleine
authors.initials: M
authors.lastname: Wéry
authors.forename: Dung Trung
authors.initials: DT
authors.lastname: Tran
authors.forename: Erik
authors.initials: E
authors.lastname: Wetterskog
authors.forename: Peter
authors.initials: P
authors.lastname: Svedlindh
authors.forename: Cheuk-Wai
authors.initials: CW
authors.lastname: Tai
authors.forename: Lennart
authors.initials: L
authors.lastname: Bergström