A novel approach to the synthesis of CoPt magnetic nanoparticles

作者：Zhang Y J; Yang Y T; Liu Y; Wang Y X; Yang L L; Wei M B; Fan H G; Zhai H J; Liu X Y; Liu Y Q; Yang N N; Wu Y H; Yang J H^*

来源：Journal of Physics D: Applied Physics , 2011, 44(29): 295003.

DOI：10.1088/0022-3727/44/29/295003

L1(0) CoPt nanoparticles with face-centred tetragonal (FCT) structure are synthesized by the sol-gel method. Differential thermal analyses show the dehydration of various water molecules and decomposition/combustion of organic groups at a temperature below 600 degrees C and melting of Co and Pt at 700 degrees C. X-ray diffraction results show a transition from face-centred cubic to the FCT phase and an increase in particle size with increasing temperature. Transmission electron microscope (TEM) images show that highly monodisperse particles are obtained. High-resolution TEM (HRTEM) images reveal the appearance of L1(0) ordered phase at temperatures above 600 degrees C. The survey scans of x-ray photoelectron spectroscopy show that no magnetic impurity is detected within the detection limit. The maximum coercivity (353 344 Am-1) is obtained for the samples heated at 800 degrees C. The relationship between the temperature and the structure is discussed and the possible growth mechanism is given in terms of atomic diffusion.

• 出版日期2011-7-27
• 单位吉林师范大学