The overarching goal of this collaborative research is to (a) elucidate the fundamental interfacial interactions between active sites, supports, reactants, and reaction media, and (b) use this understanding to create materials with the best properties of homogeneous and heterogeneous catalysts for efficient reductive transformations. The main hypothesis is that these interactions can be harnessed to mediate more challenging transformations under less forcing reaction conditions. Their effects, both individual and collective, on catalytic properties are systematically studied by combining selected sites and 3D-ordered mesoporous supports. Inert supports provide isolated sites, whose performance is being compared to those constructed with non-innocent surfaces that participate through substrate and reagent activation. This work combines complementary expertise in synthetic techniques, rigorous spectroscopic characterization, and mechanistic studies. Kinetic experiments and surface-sensitive dynamic nuclear polarization (DNP) solid-state NMR methods are used to benchmark interfacial catalysts with those lacking cooperativity, such as homogeneous sites or catalytic sites on inert supports. The project focuses on reduction of carbonyls (ketones, esters, acids, and amides) and phenols through hydrogenation or hydroboration, or in tandem multicatalytic reactions. These functional groups are abundant in biorenewable compounds and energy-relevant molecules, whose conversion suffers from a lack of selective and energy efficient catalytic processes.