X-Ray Spectroscopic Analysis of Electronic Properties of One-Dimensional Nanostructured Materials

This work concerns nanostructured titania (TiO2) arrays (tubes and rods) and nanoflaky MnO2/functionalized carbon nanotubes (CNT), which exhibit excellent physical and chemical properties, including a high surface area, light absorption, and efficient separation of electrons/holes. Although these nanomaterials have been extensively studied, a detailed experimental investigation of the microscopic phenomena of electron-orbital interaction, lattice structure modulation, and especially how they respond to external stimuli is lacking. Synchrotron X-ray spectroscopic techniques (X-ray emission (XE), X-ray absorption (XA), and resonant inelastic X-ray scattering (RIXS)) were utilized to elucidate the fundamental atomic and electronic structures of the metal and oxygen ions around the Fermi level (EF) of these nanomaterials. They can also be used to examine in detail conduction/valence band structures, bandgaps, electron/hole transportation, structural symmetry, the fine structure of the crystal field splitting of the d orbital, and the symmetry of ligand p orbitals. In situ X-ray spectroscopy is used with microscopic measurements to provide more details of activity during the fabrication and catalytic reaction of these one-dimensional nanomaterials. These investigations reveal their fundamental atomic and electronic properties and promote the study of advanced nanomaterials with a view to develop the next generation of energy sources and innovative environmental solutions in the pursuit of a sustainable future.