Preparation and Property of CoFe2O4 Nanofibers with Fishbone-like Structure

Zhengwang ZHU, Rui FENG, Yang LIU, Yang ZHANG, Wenhan XIE, Lijie DONG
2020 Journal of Inorganic Materials  
CoFe2O4 nanofibers with fishbone-like structure were prepared by a electrospinning method followed with high temperature calcination, using polyvinylpyrrolidone (PVP), iron nitrate nonahydrate (Fe(NO3)3•9H2O) and cobalt nitrate hexahydrate (Co(NO3)2•6H2O) as raw materials. Results show that the crystallinity and grain size of nanofibers become larger with increasing the calcination temperature. Meanwhile, the surface morphology of CoFe2O4 nanofibers changes from smooth to rough and porous. The
more » ... orphology of CoFe2O4 nanofibers exhibits a fishbone-like structure with calcination temperature exceeding 800 ℃. The diameter of the fiber is gradually decreased with the increase of calcination temperature, and the average diameter of CoFe2O4 nanofibers calcined at 900 ℃ reaches 80.3 nm. By vibration sample magnetometer (VSM) test, the saturation magnetization (Ms) of CoFe2O4 nanofibers increases with the increase of calcination temperature, and the Ms of CoFe2O4 nanofibers calcined at 900 ℃ is 87.13 A• m 2 /kg. In a result of vector network analyzer (VNA) analysis, the microwave absorption performance is significantly different with calcination temperature changing. Among them the fibers calcined at 800 ℃ have the highest wave absorption ability. The microwave absorption mechanism of CoFe2O4 nanofibers mainly includes hysteresis loss and eddy current loss. The morphology of porous and fishbone-like generated by calcination can increased the reflection loss, for the reason that this morphology is beneficial for microwave reflection multiple times on the fiber surface.
doi:10.15541/jim20190581 fatcat:bt3o7ztjpjbazerpfl5e7g7wii