Open AccessPreparation of core‐shell Zn‐doped CoFe 2 O 4 cubes @CNT composites and their absorbing performances
Author(s) -
Xue Haoliang,
Jiao Qingze,
Hao Liang,
Ni Xiang,
Wang Yajiao,
Li Hansheng,
Wu Qin,
Zhao Yun
Publication year - 2017
Publication title -
micro and nano letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.25
H-Index - 31
ISSN - 1750-0443
DOI - 10.1049/mnl.2016.0671
Subject(s) - materials science , diffractometer , composite material , doping , carbon nanotube , thermogravimetric analysis , scanning electron microscope , transmission electron microscopy , composite number , reflection loss , nanotechnology , chemical engineering , optoelectronics , engineering
Core–shell structured composites of Zn‐doped CoFe 2 O 4 cubes @CNTs were in situ synthesised using a CVD method at 450°C with Zn‐doped CoFe 2 O 4 cubes as catalysts and ethanol as carbon source. The as‐obtained products were characterised using an X‐ray diffractometer, transmission electron microscope, thermogravimetric analyser and vibrating sample magnetometer. Results demonstrated that CNTs uniformly grew on the surface of Zn doped CoFe 2 O 4 cubes to form the shell with average diameter of 20–80 nm. The average diameter of the core/shell Zn‐doped CoFe 2 O 4 @CNTs cubes range from 3 to 10 µm. The magnetic hysteresis curves of Zn‐doped CoFe 2 O 4 cubes @CNTs illustrated the strong magnetic response to a varying magnetic field and the saturation magnetisations for the composites obtained at 450 and 600°C were 33.55 and 10.05 emu g −1 , respectively. A minimum reflection loss of −9.98 dB was observed at 9.2 GHz for the Zn‐doped CoFe 2 O 4 @CNTs core/shell composites with a thickness of 2 mm. The Zn‐doped CoFe 2 O 4 @CNTs core/shell composites prepared at a higher temperature exhibited better microwave absorbing performance than the sample prepared at a lower temperature.