Fabrication of p-NiO nanoparticles/n-TiO 2 nanospheres photocatalysts and their photocatalytic performance for degradation of Rh B

The p-n junction structure has been regarded as an effective strategy to improve the photocatalytic activity due to their effectively separation of photoelectron-holes. In the paper, the p-NiO nanoparticles/n-TiO2 nanosphere photocatalysts were successfully fabricated by the hydrothermal method. The structure and morphology of the photocatalysts with p-n junction were systematically characterized by XRD, XPS, SEM, TEM, and UV-vis. And the photocatalytic performance of the photocatalysts was evaluated by the photocatalytic decomposition of Rh B under ultraviolet light irradiation. The results showed that the loading content of NiO nanoparticles in p-n junction had influence on their photocatalytic activity. And the optimal NiO loading content for p-n junction photocatalysts was determined. After the photodegradation of Rh B under UV irradiation for 70 min, the degradation rates of the TiO2@NiO-8 samples were reached to about 97.9%. The enhanced photocatalytic performance of the TiO2@NiO composites was attributed to the formation of p-n junction at interfacial interaction between NiO nanoparticles and TiO2 nanospheres, which promoted the effectively separation of photo electron-holes. Moreover, the photocatalytic mechanisms of the p-NiO nanoparticles/n-TiO2 nanospheres photocatalysts in the degradation processes were elucidated.