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PhD defence Pengcheng Huang PhD defence Pengcheng Huang The effect of the solvent environment is important for the activity and selectivity of a catalytic reaction conducted in the liquid phase. One must carefully consider the potential interactions between the solvent molecules and the reacting species as these interactions can alter mass transfer rates, reaction kinetics, product selectivity, and catalyst stability as well as the properties of the solvent including density and viscosity. As a result, these so-called solvation effects can induce a significant change in the catalytic performance. However, finding the perfect “marriage” between the solvent, reaction, and catalyst is difficult as only a few solvents can deliver the desired performance. Essentially, the best solvents to stabilize the reactants and products in the bulk might not be the optimal solvation environment for the catalyst. A promising approach could be to decouple the local reaction environment of the active sites from that of the solvent in the bulk. This can be achieved with a polymer coating that can induce a solvation effect near the active site. In this thesis, a thermal-responsive polymer (p-NIPAM) that has a lower critical solution temperature (LCST) has been employed as polymer coating on a model Pd/SiO2 catalyst to validate this concept. The effect of the solvent and polymer-induced solvation effects on the reaction selectivity and activity have been studied using the nitrite and nitrobenzene hydrogenation reactions as probe chemistries.