Magnesium oxide (MgO) electrodes for the supercapacitor applications have been prepared using automatic spray pyrolysis technique. 100 ml of 1 M aqueous Mg(NO3)2.6H2O solution was sprayed at 2 ml/min was on to the stainless SS substrate heated to 673 K. The prepared electrodes were analysed structurally by XRD, FESEM, EDX, and contact angle measurement, functional group by FTIR and electrochemically by cyclic voltammetric analyses (CV), electrochemical impedance spectroscopy (EIS) and the galvanostatic charge discharge (GCD) technique. Different peaks in XRD pattern coincide with the standard database of JCPDS 01-1235 indicating the formation of MgO. The formation of crystalline MgO has further been corroborated by EDX. The formation of MgO was studied the molecular interactions between the metal, oxygen and carbon elements though FTIR analysis. Peaks in the CV curves confirm the redox behavior of the MgO during the CV. The measured SC was as high as 202.36 Fg -1 . Superb electrochemical stability is observed at 100 mV/s scan rate. Using charge-discharge. GCD analyses show different behavior from the normal capacitors. The charging and discharging times were found nearly same for different applied currents. The observed maximum SC was 163.55 Fg -1 which is comparable with that obtained by CV.

Pristine Polypyrrole (PPy) suffers from poor structural stability and comparatively less electrochemical durability. Ruthenium oxide has been known to provide the good structural and electrochemical stability and durable performance. Present work concentrates on the impact of addition of RuCl3 during the SILAR synthesis on the specific capacitance (SC), cycling stability and the structural stability of the ruthenium oxide (RuO2) incorporated PPy hybrid flexible electrodes (HFEs). The synthesis has been carried out by using the simple successive ionic layer adsorption and reaction (SILAR) technique using stainless steel strips as flexible substrates, 0.1M pyrrole as monomer blended with different percentages of ruthenium tri chloride (RuCl3) and 30 wt % of hydrogen peroxide (H2O2) as oxidizer and oxidative polymerizing agent. The prepared HFEs were electrochemically analyzed by cyclic voltammetry (CV), galvanostatic charge discharge (GCD) and electrochemical impedance spectroscopy (EIS). The electrodes exhibit slight variation in surface morphology as the interconnected granules become small and get closely attached and then the surface is occupied with the interconnected spheres coated with PPy matrix. The observed maximum SC was found to be 1321.67 Fg -1 at 5mVs -1 in 0.2M sodium sulphate (Na2SO4). The HFE prepared with optimum concentration of ruthenium chloride (RuCl3) exhibit 86% retention of SC even after 5000 cycles. A symmetric device has been fabricated using the optimized electrodes which has SC of 71.5 Fg -1 at 18.18 Ag -1 . The device also retains 86.05 % of the SC even after 5000 cycles. The measured specific energy and power were 286.18 Whg -1+ and 36.36 Wg -1 respectively.