Efficient photocatalytic removal of nitric oxide with hydrothermal synthesized Na0.5Bi0.5TiO3 nanotubes

•Na0.5Bi0.5TiO3 nanotubes were prepared via a facile hydrothermal route.•The Na0.5Bi0.5TiO3 nanotubes exhibited superior photocatalytic performances for the removal of nitric oxide.•The Na0.5Bi0.5TiO3 nanotubes show potential for indoor and outdoor air purification.

In this study, Na0.5Bi0.5TiO3 nanotubes were synthesized with a facile hydrothermal method using TiO2 P25 (Degussa) and bismuth citrate (BiC5H6O7) as precursors in concentrated NaOH and ammonia alkali solution. The samples were systematically characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). The as-prepared Na0.5Bi0.5TiO3 nanotubes exhibited superior activity for photocatalytic removal of gaseous nitric oxide (NO) over TiO2 P25 (Degussa) under simulated solar-light irradiation, the NO removal rate can reach as high as ca. 200 ppb·min−1 over the Na0.5Bi0.5TiO3 nanotubes in a continuous reactor with an initial NO concentration of 400 ppb. The intrinsic hollow-nanotube structure of the Na0.5Bi0.5TiO3 photocatalysts contributes to its superior activity under simulated solar light. This work provides a facile route to prepare Na0.5Bi0.5TiO3 nanotubes and suggests that the Na0.5Bi0.5TiO3 nanotubes are ideal candidates for efficient removal of nitric oxide in indoor/outdoor air.