Nitrogen-doped perovskite-type La2Ti2O7 decorated on graphene composites exhibiting efficient photocatalytic activity toward bisphenol A in water

Nitrogen-doped lanthanum titanate decorated on graphene sheets (GR/N-doped La2Ti2O7) used as photocatalyst was prepared by a two-step process. To synthesize GR/N-doped La2Ti2O7, La2Ti2O7 was initially developed under heat treatment in NH3 and subsequently decorated on GR by hydrothermal processing. The resulting GR/N-doped La2Ti2O7 was characterized by scanning electron microscopy, transmission electron microscopy, atomic force microscopy. X-ray diffraction. Raman spectroscopy, and X-ray photoelectron spectroscopy. Characterization results indicated that N-doped La2Ti2O7 was approximately 6-8 nm thick with single-crystalline perovskite structure and chemically attached onto GR nanosheets by the formation of Ti-N bond, Ti-C bond, and oxynitrides. The application of GR/N-doped La2Ti2O7 composites to bisphenol A decomposition exhibits high photocatalytic efficiency under irradiation compared with pure La2Ti2O7 materials. This finding was due to the synergistic effect of great adsorption, enhanced light absorption, efficient charge separation and transfer processes in the presence of GR, and reduced band gap energy because of N doping. This study provides new insights into the fabrication and practical application of high-performance photocatalysts in wastewater treatment. (C) 2015 Elsevier Inc. All rights reserved.