Despite their high theoretical specific energy of 2,600 Wh kg-1, the commercialization of Li-S devices is hindered by irreversible capacity loss from the dissolution of polysulfide intermediates in the electrolyte solution. We report novel strategies to design reactive sites for polysulfide adsorption in metal-organic frameworks (MOFs) to improve capacity retention and ionic conductivity. Incorporation of redox-active moieties in the framework further enable fast charge and discharge capabilities. Identifying structure-property-function relationships in tunable molecular platforms offer new methods to advance electrochemical storage technologies. In addition, we will present new strategies to probe the electrode-electrolyte interfaces in electrocatalysis using advanced electrochemical techniques such as in-situ vibrational spectroscopy and electrochemical impedance spectroscopy. The ubiquity of surfactants and carbon supports in catalysis warrants a closer examination on their influence on the electrode-electrolyte interface during carbon dioxide reduction. New insights on the impact of molecular additives and carbonaceous materials on product formation and Faradaic efficiency in electrocatalytic carbon conversion will be discussed.