Overview of nanostructured metal oxides and pure nickel oxide (NiO) electrodes for supercapacitors: A review

At present world facing major problems of rapid growth of population and global economy due to this demand for energy consumption has been considerably increased. Supercapacitor devices are emerging as one of the promising energy devices for the future energy technology. In this regards, the transition metal oxides are suitable electrode materials for pseudocapacitors due to different oxidation states and different ions. In this review article, we focused on the pure nickel oxide based materials synthesizing by various synthetic methods. Nowadays nickel oxide is emerging electrode material for energy storage application due to its thermal stability, high chemical stability, high theoretical specific capacity, low price, naturally abundant and environment friendliness. There are three important factors on which performance of supercapacitor mainly depends on namely electrochemical properties of the electrode material, electrolyte and voltage range. In this review paper, storage mechanism of supercapacitors with their types, characteristics of the electrode material, different synthesis methods of nickel oxide electrode material and different electrolyte materials have been reported.