Hydrothermal synthesis of a nanostructured TiO2-based material in the presence of chitosan

Abstract

Quasi-one-dimensional TiO2-based nanostructures have been produced through hydrothermal treatment-without additives and in the presence of chitosan—of anatase nanopowder synthesized by an electrochemical sol-gel process. The morphology, phase composition, and structure of the hydrothermal synthesis products were studied by various physicochemical characterization techniques, including high-resolution electron microscopy, X-ray diffraction, and IR spectroscopy. The results demonstrate that the forming one-dimensional structures are isostructural with β-titanic acid, H2Ti3O7. Heat treatment at t ≥ 500°C yields a mixture of sodium polytitanates, NayTixO2x + 1, with y = 0.5–2 and x = 2–5. The surface morphology and shape of the nanostructures persist up to 700°C. The key features of the formation of quasi-one-dimensional TiO2-based structures in the presence of chitosan have been identified.