ABSTRACT
Energy crisis due to the limited source of fossil fuels, increasing demand of energy day by day and above all global warming issue have compelled human being to think about the renewable and sustainable energies. Researchers are intended to develop, efficient energy conversion devices based on the solar energy, wind energy, geothermal energy etc. The problem is that in the night there is no sun and wind does not blow on our demand, therefore we are simultaneously required highly efficient energy storage devices to fulfil our requirement of 24 hrs. Among all supercapacitors or electrochemical double-layer capacitors or ultracapacitors have shown a great promise as a future and the last generation energy storage devices. Supercapacitors are bridging storage devices between capacitors with high power density and batteries with high energy density. These electrochemical double-layer capacitors are energy storage devices with high power density, high charging/discharging rate and very long cyclic life but relatively low energy density than batteries. The only motive is to increase the energy density (which depends on the electrode materials) by utilizing new and efficient electrodes. Therefore, designing of an efficient device demands the synthesis and detailed study of the various materials. Iron-based materials, such as Fe2O3, Fe3O4, FeOOH, FeS and FeS2, have received considerable attentions due to their theoretical high electronic capacitance, environmental benign, abundance in nature and economical than other materials. Although it has low electrical conductivity and high electrochemical instability. In recent years important advances have been made in the use of iron-based materials as a negative electrodes in supercapacitors. This chapter focuses on the recent research on the synthesis, design and commissioning of iron-based materials for electrode in supercapacitors for high performance.
