New Horizons in Computational Modeling of Polyoxometalates: Biological Activity, Energy Storage and Sustainable Catalysis

Identifier:  TDX:3724

Handle: https://hdl.handle.net/20.500.11797/TDX3724

Authors:  Solé Daura, Albert

Abstract:
Polyoxometalates (POMs) constitute a family of polynuclear metal oxide clusters that are usually built up from W, Mo or V in their highest oxidation state. Owing their molecular and electronic features, POMs have shown applicability in a wide variety of fields. Among them, this thesis covers computational studies aimed to understand the role of POMs in applications related to biochemistry, energy storage or catalysis. The discussion can be divided in three well-differentiated parts. The first one deals with the interaction of POMs with biological systems. Specifically, we have characterized the nature of the POM···protein interactions at atomistic level, as well as their physicochemical foundations, using molecular dynamics simulations. This survey also evaluates how the affinity of POMs towards biological systems is influenced by several parameters of the POM structure. Furthermore, we studied two examples of reactivity between POMs and proteins. These are the selective hydrolysis of peptide bonds by Zr-containing POMs and the reduction of disulfide bridges promoted by reduced POMs, which has been investigated together with experimental collaborators. The second topic links with redox properties of POMs. In particular, we have analyzed the reasons for the experimentally observed electrochemical reduction of POMs beyond their previously known limits, which is tightly related to the collective behavior of POMs in solution. Finally, and in collaboration with several experimental groups, we report the most recent advances in the computational modeling of the alkene epoxidation reaction catalyzed by Nb- and Ti-substituted POMs. Notably, these oxidations take advantage of hydrogen peroxide as environmentally friendly terminal oxidant that generates water as sole by-product. Overall, this work represents a step forward in the computational modeling of POMs and further probes the capability of computational methods to provide accurate answers to complex questions arising from the latest progresses in chemical research.