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تسجيل مستخدم جديدTunable electronic structure and stoichiometry dependent disorder in Nanostructured VO$_x$ films
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We present and discuss an original method to synthesize disordered Nanostructured (NS) VO$_x$ films with controlled stoichiometry and tunable electronic structures. In these NS films, the original lattice symmetry of the bulk vanadium oxides is broken and atoms are arranged in a highly disordered structure . The stoichiometry-dependent disorder as a function of the oxygen concentration has been characterized by in-situ X-ray Absorption Near-Edge Structure (XANES) spectroscopy identifying the spectroscopic fingerprints. Results show structural rearrangements that deviate from the octahedral symmetry with different coexisting disordered phases. The modulation of the electronic structure of the NS films based on the resulted stoichiometry and the quantum confinement in the NS particles are also discussed. We demonstrate the possibility to modulate the electronic structure of VO$_x$ NS films accessing new disordered atomic configurations with a controlled stoichiometry that provides an extraordinary opportunity to match a wide number of technological applications.
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