Presence of Room Temperature Ferromagnetism in CO2+ Doped TiO2 Nanoparticles Synthesized through Shape Transformation
AutoriKuljanin-Jakovljević, Jadranka Ž.
Radoičić, Marija B.
Članak u časopisu
MetapodaciPrikaz svih podataka o dokumentu
New approach for synthesis of Co2+ doped TiO2 nanoparticles showing room temperature ferromagnetic behavior, through shape transformation of hydrothermally treated scrolled titania nanotubes in the presence of Co2+ ions is described. The XRD and ICP measurements demonstrated successful incorporation of 0.46 at % Co2+ ions in preserved anatase crystal structure of TiO2 nanoparticles, without presence of Co-oxide Clustering, metallic Co, or Various Co-Ti oxide species. HRTEM measurements revealed that majority of the nanoparticles have polygonal shapes with average dimension of similar to 6-10 nm. Obtained Value of 3.06 eV for band gap energy of Co2+ doped TiO2 nanoparticles explained altered optical properties of TiO2 matrix and indicates narrowing of the electronic properties in respect to the undoped anatase TiO2 nanomaterials. The Co2+ doped TiO2 nanocrystals enabled synthesis of optically transparent film that shows room temperature ferromagnetic ordering with a saturation magnetic ...moment of 0 25 mu B per Co atom The proposed explanation for room temperature ferromagnetic behavior is based oil the presence of critical amount of oxygen vacancies that mediate interaction between Co2+ spins trapped in the lattice Structure of titania nanoparticles with undercoordinated surface defect sites.
Izvor:Journal of Physical Chemistry. C, 2009, 113, 50, 21029-21033
- Serbian Ministry of Science and Technological Development , NCEM, Office of Science, Office of Basic Energy Sciences of the US Department of Energy [DE:-AC02-05CH11231], Spanish MEC f