Novel materials and devices for energy storage

An increase in the demand for clean and sustainable energy storage with a high power density, along with a long cyclic life time has made supercapacitors an emerging energy storage device. However, one of the main challenges of today's world is to develop energy storage devices which are environmental friendly, cost effective, and which posses an excellent storage capacity. Therefore, this thesis presents the experimental results of utilizing nickel nanoparticle impregnated carbonized wood as a potential electrode material for supercapacitor applications. The electrode was synthesized by carbonizing the nickel nitrate impregnated wood at 900oC for an hour. The concentration of nickel nanoparticles in the carbonized wood was varied by changing the concentration of nickel nitrate solution. The surface morphology and the structure of the electrodes as prepared were studied by using X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), and X-ray Photoelectron Spectroscopy (XPS). Electrochemical characterization such as Cyclic Voltammetry showed the presence of peaks indicating a psuedocapacitive behavior of the electrode. The Galvanostatic charge-discharge measurements showed nonlinear charge-discharge curves with changes in the slope. From the electrochemical measurements, it is observed that the electrode material exhibited a specific capacitance of 3616 F/g and a power density of 30 kW/kg along with an excellent capacitance retention of greater than 80% after 6000 charge-discharge cycles. These results indicate that the nickel nanoparticle impregnated carbonized wood could be one of the potential electrode materials for supercapacitor applications.