CoxTi1－xO2－δ体材中氢退火引起的铁磁性及结构相变

摘要: Paramagnetic (Co 3 O 4 ) x/3 (TiO 2 1- x (0 and TiO from 700 ℃ to 1000 in air. X-ray diffraction (XRD) re sults showed that perovskite CoTiO existed all samples. Anatase p hase was also detected samples sintered at when sintering the mixt ure above 900 ℃, rutile phase formed with anatase disappearing. All sa mples exhibited room-temperature ferromagnetism (RTFM) after being hydrogenated 10％ H /Ar mixed atmosphere for 1 hour 500 ℃. photoelect ron spectroscopy (XPS) Co +2 formal oxidation state, no clusters were detected. XRD disappeared a new Ti 1-x 2-δ hyd rogenation. It is suggested hydrogenation causes transformation f rom . RTFM of sample originates intrinsic The exchange interaction between 2+ occ urring may be essential reason RTFM.