Magnetic properties and heat capacity of CoTiO₃ nanopowders prepared by stearic acid gel method

摘要

Pure cobalt titanate nanopowders were successfully prepared in wet-chemistry synthesis method, using cobalt acetate and tetra-n-butyl titanate as Co and Ti sources and stearic acid as complexing reagent. The gel was calcined at different temperatures in air ranging from 500°C to 650°C. Results of thermal analysis are given; including both differential thermal gravimetry (DTG) and thermogravimetric. X-ray diffraction was used to characterise the crystallisation process, the particle size and morphology of the calcined powders. The results indicated that cobalt nanopowders with a particle size of about 35 nm could be obtained after calcinations of the dried gel at 600°C for 2 h. In the temperature range between 80°C and 500°C, the empirical equation (C _P (JK−1 mol−1) = −136.311 + 0.141 T − 3.551 × 107/T 2) for the C _P of CoTiO₃ was determined from differential scanning calorimetry. The synthesised CoTiO₃ indicate a superparamagnetic behaviour, as evidenced by using vibrating sample magnetometer at room temperature.View full textDownload full textKeywordsnanostructures, sol-gel synthesis, X-ray diffraction, magnetic measurements, heat capacityRelated var addthis_config = { ui_cobrand: "Taylor & Francis Online", services_compact: "citeulike,netvibes,twitter,technorati,delicious,linkedin,facebook,stumbleupon,digg,google,more", pubid: "ra-4dff56cd6bb1830b" }; Add to shortlist Link Permalink http://dx.doi.org/10.1080/17458080903260936