Search

Developing an efficient, clean, sustainable, and reliable energy storage system is still a key challenge to resolve the growing demands of energy consumption. In this regard, supercapacitor becomes one of the foremost promising and emerging types of energy storage systems comprising properties of traditional batteries and conventional capacitors. Herein, a binder-free composite electrode of Al(OH)3/MnO2/FeOOH (AMFO) has been synthesized on stainless steel substrate via a facile, eco-friendly, and cost-effective Layer by Layer method at room temperature. The high resolution scaning electron microscopy reveals the mesoporous reindeer moss-like morphology of the synthesized electrode. The supercapacitive behaviour of the synthesized electrode has been explored in 1 M Na2SO4 electrolyte solution by using electrochemical measurement. The highest specific capacity of 2557 C g−1 has been obtained at a scan rate of 5 mV s−1 having wide potential range (−1.10 to 1.05 V). Further, a symmetric prototype supercapacitive device has been fabricated by coupling the AMFO electrodes. The high specific capacitance of 511 F g−1 has been obtained with ultra-high energy and power densities of ∼443 Wh kg−1 and ∼13 kW kg−1, respectively. These results indicate that this electrode has potential practical applications as a power backup, portable electronic device, and energy storage system.

Supercapacitor is one of the most promising and emerging type of energy storage devices having the merits of both conventional battery and traditional capacitor. In this regard, we have deposited Yttrium doped Strontium hydroxide thin films on stainless steel substrate with the help of a facile, cost-effective successive ionic layer adsorption and reaction technique at room temperature without using any binder. Doping of Yttrium into Strontium hydroxide enhances both electronic conductivity and electrochemical performance of the electrode for energy storage. Nanorods like structure with the tuberose morphology has been obtained with the help of field emission scanning electron microscopy. The cyclic voltammetry, galvanostatic charge-discharge and electrochemical impedance spectroscopy measurements show the pseudocapacitive battery like response. Among all the synthesised materials, 1.0 at. % Yttrium doped Strontium hydroxide shows a high specific capacity of 705.3 C g−1 at 0.4 mA current rate and stability of ∼82% at 2.5 mA current rate. The prototype light-weight solid-state symmetric supercapacitor device of Yttrium doped Strontium hydroxide electrodes has been fabricated by sandwiching PVA-Na2SO4 gel. Thus, we observe that this device has potential applications for the next-generation cost effective energy storage system.