Novel dual core@shell Fe3O4@C@polypyrrole (PPy) composite for sodium ion batteries

Abstract In present work, we synthesize the novel dual core@shell Fe3O4@C@polypyrrole (PPy) composite by two step method. The ratio of Fe3O4/C and PPy is taken in such a way that intermediate carbon layer provides an excellent electrical connectivity between Fe3O4 nanoparticles and PPy polymer. Further, these dual core/shell composite are characterized by spectroscopic and microscopic techniques. After this we have investigated it for sodium ion battery application. The composite shows discharge capacities of 64 mAh g−1 after 100 cycles and 68 mAh g−1 after 60 cycles at current densities of 1 A g−1 and 1 A g−1 respectively in the voltage range of 0.01–2.5 V.