A New Metal‐Ester Bonding Motif for the Synthesis of Hybrid Molecular Catalysts on Metal Oxide Supports Leads to Tunable Reactivity

Abstract

ABSTRACT The synthesis, characterization, and structure‐function properties for a new class of hybrid catalysts comprised of molecular catalysts with ligands covalently bound to metal oxide (MOx) supports via metal‐ester bonds is reported. Anchoring molecular catalysts to metal‐oxides through the ligand structure is an important motif for dye‐sensitized solar cells, electrocatalysis, and thermally driven catalysis. This new motif is amenable to a wide variety of metal oxide supports. Data show this new surface binding motif is able to achieve catalyst surface loadings of up to two molecules per nm 2 which is up to 60x greater than previously reported binding motifs. Catalytic reactivity trends show that the MOx support influences the molecular catalyst properties and reactivity through inductive effects. The influence of the support on catalytic properties has been correlated to the point of zero charge (PZC) of the support and shown to be predictable. Thus, this class of hybrid catalysts can be tuned by the choice of oxide support without making chemical changes to the catalyst, which will allow for reactivity beyond traditional Hammett parameter substituent changes. This allows for precise control of the catalyst nucleation, coordination environment, and accessible oxidation states, enabling highly tailored and controllable catalytic properties.