Synthesis and characterization of hybrid nanostructures produced in the presence of the titanium dioxide and bioactive organic substances by hydrothermal method

Hybrid nanostructures produced by hydrothermal treatment of TiO2 in the presence of bioactive organic substances such as chitosan, aminoterephthalic acid and their mixture have been investigated. Sodium polytitanates as one-dimensional elongated structures with lengths of several hundred of nanometers were obtained in the presence of chitosan and aminoterephthalic acid. With chitosan the elongated nanostructures are formed by successive superposition of structural fragments—nanostrips with well-ordered multilayered morphology and increased distance between successive layers to 1.2 nm. Quite different amorphous products as agglomerates with roundest and rhomboid morphology are formed when the mixture of chitosan and aminoterephthalic acid is added to the reaction system. One can propose that main reason of such behavior is a low rate of diffusion of dissolved Ti(IV) ions in the high viscous mixed chitosan–aminoterephthalic system. An effect of organic substances on the formation, morphology and transformation of various titanates is discussed.