Novel synthesis of N-doped TiO2 flower-like microspheres with excellent photocatalytic activity for removal of Cr(VI) and methylene blue

N-doped TiO2 flower-like microspheres (N-TFMs) were synthesized via a novel solvothermal method followed by calcination. It is found that the flower-like microspheres are 600–800 nm in diameter and consist of ultrathin nanosheet with a thickness of ca. 3 nm, which possess a high specific surface area up to 304 m2/g. Besides, N dopant was effectively incorporated into TFMs and no additional nitrogen source was required during calcination. The synthesized N-TFMs exhibit much higher photocatalytic activity for the removal of Cr(VI) and methylene blue than commercial P25 TiO2 under visible-light irradiation. Owing to the advantages of open-type morphology, ultrathin thickness and novel N doping, the synthesized N-TFMs maybe have a wide application prospect in environmental purification.