The composite nanofibers of SrTiO3/SrFel2O19 with a molar ratio of 1：1 and diameter about 120 nm were prepared by electrospinning. Effects of calcination temperature on the formation, crystallite size, morphology and...The composite nanofibers of SrTiO3/SrFel2O19 with a molar ratio of 1：1 and diameter about 120 nm were prepared by electrospinning. Effects of calcination temperature on the formation, crystallite size, morphology and magnetic property were studied by infrared spectroscopy, X-ray diffraction, scanning electron microscopy and vibrating sample magnetometer. The binary phase of strontium ferrite and titanate was formed after being calcined at 900℃ for 2 h and the composite nanofibers were fabricated from nanograins of SrTiO3 about 24 nm and SrFel2O19 around 33 nm. The crystallite sizes for the nanofibers increase with increasing calcination temperature and the addition of SrTiO3 has an obvious suppression effect on SrFel2O19 grain growth. The specific saturation magnetization and remanence tend to increase with the crystallite size. With increasing calcination temperature from 900 to 1050℃, the coercivity increases initially, achieving a maximum value of 520.2 kA.m^-1 at 950℃, and then shows a reduction tendency.展开更多
MnGa films were grown by magnetron sputtering on thermally oxidized Si（Si/SiO2） and glass substrates. Films grown on single-crystal Si（100） substrate with different underlayers were prepared for comparison. It is ...MnGa films were grown by magnetron sputtering on thermally oxidized Si（Si/SiO2） and glass substrates. Films grown on single-crystal Si（100） substrate with different underlayers were prepared for comparison. It is found that the Si/SiO2 substrate is more suitable for growing high-coercivity MnGa films than the glass substrate, which is the result of the isolated-island-like growth. A coercivity of 9.7 kOe can be achieved for the 10 nm MnGa films grown on Si/SiO2 substrate at substrate temperature TS of 450 °C.Optimized experimental conditions are specified by changing the thickness of the MnGa films and the temperature of the substrates.展开更多
基金supported by the National Natural Science Foundation of China (Grant No. 50674048)Research Fund for the Doctoral Program of Higher Education of China (Grant No.20103227110006)Jiangsu Provincial Postgraduate Cultivation and In- novation Project (Grant No. CX10B-257Z)
文摘The composite nanofibers of SrTiO3/SrFel2O19 with a molar ratio of 1：1 and diameter about 120 nm were prepared by electrospinning. Effects of calcination temperature on the formation, crystallite size, morphology and magnetic property were studied by infrared spectroscopy, X-ray diffraction, scanning electron microscopy and vibrating sample magnetometer. The binary phase of strontium ferrite and titanate was formed after being calcined at 900℃ for 2 h and the composite nanofibers were fabricated from nanograins of SrTiO3 about 24 nm and SrFel2O19 around 33 nm. The crystallite sizes for the nanofibers increase with increasing calcination temperature and the addition of SrTiO3 has an obvious suppression effect on SrFel2O19 grain growth. The specific saturation magnetization and remanence tend to increase with the crystallite size. With increasing calcination temperature from 900 to 1050℃, the coercivity increases initially, achieving a maximum value of 520.2 kA.m^-1 at 950℃, and then shows a reduction tendency.
基金financially supported by the National Natural Science Foundation of China (Nos. 51590883, 51471167, 51271179 and 51571194)the project of Chinese Academy of Sciences with grant number KJZD-EW-M05-3supported by a Joint Research Project from Ministry of Science, ICT and Future Planning/Korea Research Council for Industrial Science and Technology
文摘MnGa films were grown by magnetron sputtering on thermally oxidized Si（Si/SiO2） and glass substrates. Films grown on single-crystal Si（100） substrate with different underlayers were prepared for comparison. It is found that the Si/SiO2 substrate is more suitable for growing high-coercivity MnGa films than the glass substrate, which is the result of the isolated-island-like growth. A coercivity of 9.7 kOe can be achieved for the 10 nm MnGa films grown on Si/SiO2 substrate at substrate temperature TS of 450 °C.Optimized experimental conditions are specified by changing the thickness of the MnGa films and the temperature of the substrates.
