Heterobimetallic Lanthanide and Actinide Alkoxides as Single-Source Precursors for the Development of Nanomaterials

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This PhD thesis presents new insights into the synthesis of lanthanide and actinide alkoxides, detailing the creation of homo- and heteroleptic bimetallic lanthanide alkoxides [LnM(L)m(OR)nsolv] and their structural analysis based on variations in ionic radii and metal valence states. It explores the influence of the steric profiles of alkoxo ligands and the presence of donor ligands in the coordination sphere. Notably, despite the expected ionic character of Ln-O and An-O bonds, these mixed-ligand complexes exhibit impressive volatility, positioning them as promising single-source precursors for gas phase deposition of oxide phases. The thesis reports the successful deposition of thin films of pyrochlore Nd2Sn2O7 through both liquid and gas phases using [NdSn(OtBu)5py] and [NdSn(L)(OtBu)4] as molecular sources. Additionally, sols derived from mixed-metal Nd-Sn compounds were electrospun into single-phase Nd2Sn2O7 nanofibers, with their photocatalytic and sensing properties examined. A bilayered (Nd2Sn2O7//Fe2O3) photoanode demonstrated enhanced photoelectrochemical performance, while the Nd2Sn2O7 single layer showed high selectivity for hydrogen in gas sensing. The thesis also investigates novel heterometallic actinide(IV, V, VI) alkoxides, including the first monomeric pentavalent uranium tert-butoxide [U(OtBu)5py], achieved through innovative synthetic strategies leveraging the Lewis basicity of Sn(II) compounds.