Molecularly functionalized surface of plasmonic heterostructures for sustainable and selective reduction of carbon dioxide

Abstract

Hybrid technology is a significantly attractive and rapidly growing research theme because it can merge the advantages of each desired material to develop an improved material especially in terms of efficiency and sustainability. Heterogenization of the homogeneous catalysts has been the promising strategy because the specific catalytic activity of the homogeneous catalysts can be maintained over times or environmental stimulus. In this dissertation, several covalent linkages are used to chemically functionalize the surface of the heterogeneous nanomaterials. The covalent immobilization can provide precisely controlled highly durable and site-specific conjugation at a molecular level. As a result, a molecular catalyst which selectively converts $CO_2$ into formic acid was successfully immobilized via phosphonate ($-PO_3H_2$) linkages on the $Au$/$TiO_2$ heterostructure to exhibit high reaction rate and sustainability. In addition, the surface of Au nanoparticles was directly passivated by N-heterocyclic carbene (NHC)-RuCY monolayer to prevent side reactions and stabilize the immobilization. Therefore, this dissertation strongly suggests the covalent surface modification and immobilization of homogeneous molecular catalysts as a promising and highly material-adaptable strategy to construct a hybrid photocatalyst to enhance the catalytic activity and sustainability.