Tailoring the Electrocatalytic and Supercapacitor Performance Through Materials Design and Nano-engineering

The development of efficient energy conversion and storage systems using electrochemical solutions heavily depends on selecting the right electrode material. This involves meticulously designing and tailoring the material's functionality to achieve the necessary surface and intrinsic interfacial characteristics. The aim of this thesis is to provide insights into electroactive material design criteria and offer a range of catalyst preparation methods to achieve this goal. The study has also delved into several fundamental catalysis and material synthesis aspects. In this context, we have demonstrated the versatile use of Lewis base-containing porous organic polymers as a dual-function support and stabilizer for a Pt single atomic/ionic active sites-based hydrogen evolution electrocatalyst, resulting in superior catalyst mass activity and utilization. Additionally, a highly efficient synergistic graphene-supported Ni(OH)2/Zr(OH)4 nano clusters-based oxygen evolution electrocatalyst was developed through the use of a sacrificial metal-organic framework as a pre-catalyst to regulate the release of active catalyst precursors. The thesis also explored the ability of Ag/PCA organic-inorganic hybrid catalyst material to control the oxygen reduction reaction pathway with enhanced selectivity towards peroxide formation, where such hybrid material was obtained through a novel bio-nanosynthesis route. The significant role of particle dispersity and proximity effects in evaluating CuO nanostructure-based electrocatalysts with pristine surfaces, obtained through the superior Leidenfrost nano synthesis technique, was also addressed. The studies in this work also investigated the overlooked role of the conjugate anions in controlling the nanocellulose-derived carbon aerogel microstructures and their impact on performance in EDLC electrodes. Furthermore, the study revisited the important role of surface wettability and the correlation between electrolyte selection and aerogel microstructure and surface characteristics in defining the EDLC active material performance.