Structure and magnetic properties of iron-platinum particles with γ-ferric-oxide shell

Nanoparticles of solid solution Fe (x) Pt(1-x) , where 0.25a parts per thousand yenxa parts per thousand yen0 ( fcc lattice) with gamma-Fe(2)O(3) shell (lattice of the spinel type) were synthesised and characterised by high-resolution transmission electron microscopy, energy dispersive X-ray analysis, electron energy loss spectroscopy, Mossbauer spectroscopy and magnetometry. From the point of view of magnetic properties, such two-phase particles are interesting because their core is antiferromagnetic or paramagnetic (at very small values of x) whereas the shell is ferrimagnetic. The size of the particles was in the range of several nanometers. The Mossbauer measurements revealed a blocking temperature of about 100 K above which the particles are superparamagnetic. Towards lower temperatures, the magnetic characteristics of an ensemble of such particles show an increase of magnetic rigidity

Rational assembly and dual functionalization of Au@MnO heteroparticles on TiO2 nanowires

Au-MnO heteroparticles were immobilized on the surface of TiO2 nanowires and tagged subsequently with a fluorescent ligand. The immobilization of the Au@MnO heteroparticles was achieved by functionalizing the TiO 2 nanowire support with a polymer containing catechol anchor groups for binding to the metal oxide surface and amine groups for conjugation to the Au domains of the Au@MnO heteroparticles. The Au domain of the resulting TiO2@Au-MnO nanocomposite could be functionalized selectively with a thiol-tagged 24 mer oligomer containing Texas red (SH-ODN-TXS red), whereas a green dye (NBD-Cl) could be anchored selectively to the TiO2 "support" using the free amine groups of the polymeric ligand. The binding of the NBD and the Texas red fluorophors was monitored by confocal microscopy and the functionalization of the metal oxide nanoparticles was monitored by UV-Vis spectroscopy. All composite products were characterized by transmission electron microscopy (TEM) combined with energy dispersive X-ray spectroscopy (EDX), confocal laser scanning microscopy (CLSM) and UV-Vis spectroscopy. © 2014 The Partner Organisations

Recyclable nanobiocatalyst for enantioselective sulfoxidation: Facile fabrication and high performance of chloroperoxidase-coated magnetic nanoparticles with iron oxide core and polymer shell

Journal of the American Chemical Society1313612892-12893JACS