Preparation and Photocatalytic Performance of Hollow Structure LiNb3O8 Photocatalysts

Hollow structure LiNb 3 O 8 photocatalysts were prepared by a hydrothermal method assisting sintering process. The particles’ aggregation to form hollow structures with obvious cavities can be attributed to the Li element volatilization during calcination process. All the LiNb 3 O 8 powders show high photocatalytic efficiency of degradation of methylene blue (MB), especially for the sample calcined at 700 °C (LNO700), with only 3 h to completely decompose MB. The photo-degradation of MB follows the pseudo-first-order kinetics, and the obtained first-order rate is 0.97/h. The larger degradation rate of LNO700 can be attributed to its hollow structure which provides a larger specific surface area and more active sites to degrade the MB molecules. The cycling test of photo-degradation and adsorption of MB over LNO700 powder indicates that the hollow structure of the LiNb 3 O 8 photocatalyst is stable and the LiNb 3 O 8 photocatalyst is an efficient photocatalyst with good reusability, confirmed by the XRD and X-ray photoelectron spectroscopy tests before and after photo-degradation of MB.