Electrochemical energy storage performance of Fe(Co)2S4 directly grown over Ni foam substrates
The thirst for energy sources began right from human evolution, and it is unquenchable. Energy storage came into existence because of a couple of reasons such as,
1. Population α Pollution,
2. Demand ≠ Supply.
As soon as energy storage crisis sprouted, scientists began their race towards inventing new energy storage devices (ESD’S). The fascinating and conventional ESD’S are batteries and capacitors. A capacitor is always known for its quick charging and discharging property. The recent trend of the research in energy storage is to improve the energy density and power density of capacitors at low cost. Then bloomed the development of electrochemical capacitors or supercapacitors. Supercapacitors have higher power density compared to batteries. Based on the charge storage mechanisms, Supercapacitors can be divided into two categories, namely, electric double layer capacitors (EDLCs) and pseudocapacitors. Based on the charge storage mechanisms, they can be divided into two categories, namely, electric double layer capacitors (EDLCs) and pseudocapacitors. At present, the new target for the researchers is to find a suitable electrode material to improve the efficiency of a pseudocapacitor. Transition metal oxides and sulfides are considered as excellent electrode materials for pseudocapacitors as they can provide a variety of oxidation states for efficient redox charge transfer. Also, the precedent journals portray that bi-metal sulfides give better performance than bi-metal oxides.
In the present study, a ternary chalcogenide, i.e., iron-cobalt sulfide (Fe(CO)2S4) has been selected as the electrode material.In Fe(CO)2S4, each element has its unique features such as iron (Fe) is known for its high electrical conductivity, cobalt (CO) is known for its high specific capacitance, and sulfur is known for rich redox states. The material Fe(CO)2S4 has been successfully in-situ grown on nickel foam by hydrothermal method.