Anodic titania nanotubes (TiO
2-NT) are very promising for use in photocatalysis and photovoltaics due to their developed surface, symmetrical structure and conductive properties, which, moreover, makes them a convenient matrix for creating various nanocomposites. Herein we propose a new facile way
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Anodic titania nanotubes (TiO
2-NT) are very promising for use in photocatalysis and photovoltaics due to their developed surface, symmetrical structure and conductive properties, which, moreover, makes them a convenient matrix for creating various nanocomposites. Herein we propose a new facile way of synthesizing symmetrical TiO
2-NT followed by a modification with barium titanate (BaTiO
3) nanoparticles, combining the advantages of electrochemical oxidation and hydrothermal synthesis. The electrophysical and optoelectronic properties of the formed nanocomposites have been studied. An asymmetry of the current–voltage characteristics was revealed. It is shown that during the barium titanate deposition, a symmetry-breaking nanoheterojunction TiO
2/BaTiO
3 is formed. Using EPR spectroscopy, paramagnetic defects (titanium, barium and oxygen vacancies) in the samples were determined. It was observed for the first time that upon illumination of titania nanotubes modified with BaTiO
3, the asymmetrical separation of photoexcited charge carriers (electrons and holes) between TiO
2-NT and BaTiO
3 occurs, followed by the capture of electrons and holes by defects. As a result, the photoinduced charge accumulates on the defects.
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