Novel Organic and Inorganic Materials for High Efficiency Electrochemical Energy Storage and Conversion

Abstract

The thesis is devised to address the two very important energy related aspects of energy storage and hydrogen generation as per the current scientific trend. In the first part of thesis work a new organic Li ion electrode material in the form PTCDA (perylene 3, 4, 9,10-tetracarboxylic dianhydride) based Polyimide is proposed as highly stable anodematerial for Li ion energy storage. Higher Li-ion storage compared to other Polyimides is shown to be driven by the presence of carbonyl groups. We got maximum capacity of 800 mAh/g for Anthraquinone based polyimide (PI-I) for the applied current density of 100 mA/g, the high capacity is due to the reaction of carbonyl group with lithium and also with the pi bonds present in the polymer. We also got very good cyclic stability of about 100% of its reversible capacity retention after 100 cycles and more than 85% capacity retention after 500 cycles for the applied current density of 1A/g and 3A/g, respectively. In the 2nd part of this thesis synthesis of aligned Nickel Cobalt Phosphide (NCP) nano needles on carbon fiber paper for the first time is being demonstrated as an efficient catalyst for HER. The direct hydrothermal growth of the NCP catalyst on carbon fiber paper is shown to compare well with present state of art HER catalysts. The impressive HER parameters including low over potential of 73mV for achieving the HER current density of 10mA/cm2 and smaller Tafel slope of 55mV/dec are attributed to direct growth of NCP nanowires on the conducting carbon substrate.