Executive Summary : | The primary aim of this project is the systematic design, synthesis and characterization of two fundamentally novel classes of compounds and their utilization as heterogeneous catalysts in various fundamentally important reactions: (i) The synthesis of the first class of compounds will involve the utilization of Polyoxo-Noble-Metalates (PONMs), which are anionic noble-metal-based nano oxo-clusters formed out of Pd(II), Au(III), Pt(II/IV), and conventional transition-metal-based Polyoxometalates (POMs), which are anionic metal–oxo polyanions generally formed out of the connectivity between oxide anions and early d-block elements [V(V), Nb(V), Ta(V), Mo(VI), W(VI), Zr(IV), Hf(IV), Ti(IV)], as dual vertices in the construction of stable, porous and multi-functional Metal-Organic Frameworks (PONM-POM-MOFs) utilizing suitable organic linkers with functional groups that can cap and interconnect the two vertices. The integration of POMs, which are known to be efficient proton relays and act as Lewis acids or bases depending on the conditions, and the catalytically active noble-metal oxo-clusters in a single stable heterogeneous MOF system, is expected to lead to materials that would be catalytically active in various organic oxidations and coupling reactions. In addition, inherently noble metal oxo-cluster-based porous and stable MOFs are few in number, and thus, are not well studied. (ii) The synthesis of the second novel class of materials would involve the reaction of various pre-formed p-aminophenyl-functionalized POMs with various bipyridine and phenanthroline-based dicarbaldehydes leading to stable and porous MOFs through the formation of imine bonds. The resulting MOF material would be modified by anchoring noble-metal ions, such as Rh(I), Pd(II), Ru(II), Re(I), Ir(III) to the coordinatively free bipyridine and phenanthroline moieties. Thus, the integration of the POM electron/proton relays, photoactive organic linkers, and single metal-ion catalytic sites in a stable heterogeneous system would lead to materials that are expected to be catalytically active in photo-/electrocatalytic CO₂ reduction reaction, water oxidation as well as various organic coupling reactions. |