A alkalescent route for synthesis of titanate nanosheets modified with reduced graphene oxide for enhanced photocatalytic activity

Layered titanate nanosheets (TNS) were directly synthesized by one step in a special reaction system called weak base hydrothermal system, without organic stabilizer and washing or proton exchange. Reduced graphene oxide (rGO)/TNS nanocomposites were synthesized by improved hydrothermal treatment. The obtained samples were characterized by Scanning electron microscope, Transmission electron microscope, X-ray powder diffraction, Raman spectrum, Fourier Transform Infrared spectra, UV–Vis diffuse reflectance spectrum, Photoluminescence, X-rayphotoelectron spectroscopy, X-band electron paramagnetic resonance. The results confirmed that titanate nanosheets were homogeneously dispersed on rGO sheets, and three factors play an important part in the high photocatalytic performance of the samples, including the formation of a Ti–O–C bond expanding the light wavelength absorption range, the adsorption of contaminant molecules, the high separation rate of electron–hole pairs based on the sufficient contact of TNS and rGO nanosheets. The photocatalytic performance of as-prepared rGO/TNS nanocomposites were evaluated by degradation of methylene blue under visible-light irradiation (λ ≥ 400 nm). The acquired results showed that the photocatalytic performace of rGO/TNS nanocomposites were better than that of pure TNS. It could be attributed to the phenomenon that the photogenerated electrons in TNS were easily transferred to the rGO sheets via Ti–O–C between TNS and rGO. This process decreases the recombination rate of electron–hole pairs and lead to the improvement of photocatalytic activity.