非表示:
キーワード:
-
要旨:
In this contribution, we report the chemical synthesis of carbon coated,
silica supported Co2FeGa (Co2FeGa-SiO2@C) nanocomposite particles. The
particle size of Co2FeGa particles can be tuned by varying the amount of
silica supports. The dependences of the crystal structure and magnetic
properties on particle size have been investigated by synchrotron
radiation based X-ray diffraction (XRD), X-ray absorption fine structure
(XAFS) spectroscopy, transmission electron microscope (TEM), Fe-57
Mossbauer spectroscopy, and superconducting quantum interference device
(SQUID). The superparamagnetic critical size of Co2FeGa Heusler
nanoparticles is found to be similar to 17 nm by correlating the TEM
derived particle size distribution to the Mossbauer spectroscopy data.
The effects of silica supports and carbon coating on the formation of
Co2FeGa nanoparticles of various sizes are also discussed.
