Open AccessMicrostructure and magnetic properties of the cobalt ions implanted TiO2 films
Author(s) -
Peng Ding,
FM Liu,
XA Yang,
JQ Li
Publication year - 2011
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.60.036803
Subject(s) - materials science , high resolution transmission electron microscopy , transmission electron microscopy , anatase , annealing (glass) , microstructure , ferromagnetism , thin film , scanning electron microscope , ion , sputter deposition , cobalt , analytical chemistry (journal) , sputtering , nanotechnology , composite material , condensed matter physics , metallurgy , photocatalysis , chemistry , organic chemistry , biochemistry , physics , chromatography , catalysis
TiO2 thin films were prepared by direct current magnetron sputtering on glass substrates, then were implanted by cobalt ions, and finally annealed at 500 ℃ for 50 min. Specimens for transmission electron microscopy were prepared by peeling-scattering technology, and were observed in situ by scanning electron microscopy (SEM), energy dispersive X-ray (EDX) and high resolution transmission electron microscopy (HRTEM). The films were identified as anatase structure. The Co ions exist mainly in a thin layer beneath the surface of the films. The implanted Co ions damage the TiO2 crystals and some of them exist as CoO. The annealing treatment could repair the TiO2 grains and make the Co ions diffuse into the TiO2 lattice. The vibrating sample magnetometer (VSM) measurements show that the Co ion implanted TiO2 films are ferromagnetic at room temperature and the annealing treatment in vacuum could enhance the ferromagnetism, which could be explained within the scope of the BMP theory.