Synthesis of well ordered mesoporous Yb, N co-doped TiO2 with superior visible photocatalytic activity

Well-ordered mesoporous TiO2 co-doped with nitrogen and ytterbium was successfully synthesized by an evaporation-induced self-assembly process. The as-prepared and calcined mesoporous TiO2 materials were characterized by X-ray diffraction, transmission electron microscope, UV–vis absorbance spectroscopy, X-ray photoelectron spectroscopy, fourier transform infrared and N2 adsorption–desorption measurements. After calcinations at 350 °C, the TiO2 co-doped with nitrogen and 3% ytterbium had the highest surface area (219 m2 g−1) and retained ordered structures. Under visible light irradiation, 75% of 20 mg/L phenol solution was degraded after 10 h and 10 mg/L rhodamine B (RhB) was decomposed completely after 4 h. The significant enhancement in the photocatalytic activity of the modified TiO2 is attributed to the synergistic effect of N and Yb. The N dopant extended the absorption to visible region and the Yb dopant was beneficial in stabilizing the mesoporous structure and restraining the recombination of photogenerated holes and electrons.

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► Ordered mesoporous Yb, N co-doped TiO2 was successfully synthesized.
► The nitrogen dopant enhanced the absorption in the visible region.
► The ytterbium dopant stabilized the ordered mesoporous structure.
► The ytterbium dopant reduced the recombination of holes and electrons.
► The 3.0Yb/N-TiO2 showed higher visible photocatalytic activity than pure TiO2.