Effect of microwave heating on the structure, morphology and photocatalytic activity of hydrogen titanate nanotubes

• Titania nanotubes (TNTs) were prepared in autoclave by hydrothermal method.
• The prepared TNT was annealed in microwave at different temperatures.
• The TNT was characterized by thermal, TEM, XRD, EDX, FTIR and Raman techniques.
• The catalytic activity of TNTs was tested in the photodecolouration of RB dye.
• The best activity was due to the 300 °C sample because of surface OH group.

Microwave annealing was employed to prepare well defined titanate nanotubes after hydrothermal treatment of titania precursor at mild conditions. The microwave annealed samples were used for the enhancement of UV-light-driven photocatalysis capabilities of Rose Bengal from liquid phase. The structural and catalytic activity changes were studied as a function of microwave annealing temperature. Different characterization techniques such as thermal and spectroscopic techniques were employed to characterize the as-prepared and microwave annealed samples. Characterizations confirmed the formation of hollow layered titanate nanotubes with diameter of ≈11–13 nm and several millimeter in length in the as prepared samples. Titanate was the main structure of the prepared hollow nanotubes. These nanotubes undergo a partial collapse after elevating the microwave temperature to 450–550 °C. Moreover, all the nanotubes were converted to nanoparticles after 600 °C with particle size ranged between 9 and 16 nm. The prepared samples showed significant catalytic performance in the photo oxidation of Rose Bengal (probe reaction) under UV irradiation. Moreover, the sample heated at 300 °C presented the highest catalytic activity among the prepared samples.

Graphical AbstractFigure optionsDownload as PowerPoint slideThe titania nanotubes were prepared by hydrothermal methods and heated in a microwave at different temperatures. The samples were tested in the photodecolouration of Rose Bengal.