Facile synthesis of samarium (Sm3+) doped cobalt-iron oxide nano ferrite as an advanced electrode material for possible supercapacitor applications

Herein, we present design and fabrication of Samarium (Sm3+) doped cobalt-iron oxide ferrites nanocomposite electrode as an efficient energy storage material for supercapacitors. We employed a simple, low cost and quick one step solution combustion method to synthesize CoFe2-xSmxO4 (x = 0.0, 0.050, 0.075 and 0.1) ferrites. The morphological and structural features of synthesized CoFe2-xSmxO4 ferrites were analysed through various analytical and spectroscopic characterization methods such as scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDS), transmission electron microscope (TEM), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). These analytical techniques confirm the successful doping of Samarium (Sm3+) into cobalt-iron ferrite, and the doping does not affect the crystalline structure of pure ferrite. The electrochemical properties of the synthesized ferrites were significantly improved after Samarium (Sm3+) doping into the host cobalt-iron-oxide. The highest specific capacity about 314 F/g was achieved for CoFe2xSmxO4 (x = 0.1) composite electrode material, in comparison to pure CoFe2-xSmxO4 (x = 0) which is about 125 F/g. However, CoFe2-xSmxO4 (x = 0.1) ferrite shows a superior capacitance retention of the order of 98 % even after 5000 cycles of operation at a scan rate of 250 mV/s. The electrode material fabricated by using CoFe2xSmxO4 ferrite renders an energy density of 30.16 W h/kg at a power density of 400 W h/kg. The results obtained in presented studies opens new avenues for the fabrication high-performance electrode material for supercapacitor that could be well suited for light weight electronic devices, electric vehicles, and forthcoming generation supercapacitor applications.