Synthesis of dual-phase titanate/anatase with controllable morphology doped with nitrogen from a bola-amphiphile amine surfactant as template

In the presence of a bola-amphiphile amine surfactant, 1,12-diaminododecane (DADD), N-doped dual-phase titanate/anatase with controllable morphology was fabricated in ultrasonic system, hydrothermal condition, and ultrasonic–hydrothermal system respectively. The crystal phase, surface area, and morphology could be controlled by varying the pH values of reaction media. The materials were characterized using XRD, SEM, TEM, XPS, FT-IR, UV–vis and N2 physisorption techniques. Results suggested that both ultrasonic treatment and hydrothermal procedures are critical for the fabrication of titanate/anatase with a combination of regular morphology, large specific surface area, and high thermal stability. The introduction of DADD was significant for obtaining various morphologies, such as spherical, flower-like shape and nanowire. XPS results illustrated that DADD not only acted as a template, but also as an effective dopant by introducing N element into crystal lattice. The photocatalytic activity of samples was evaluated by the photodegradation of methylene blue. Composites with effective interstitial N-doping and largest surface area (135.8 m2/g) were obtained under neutral condition, and showed the most excellent photocatalytic activity. The extraordinary photocatalytic performance of such heterojunction could be attributed to the improved adsorptive properties resulting from the large surface area of the composite, and efficient excitation via interstitial N-doping.