Improved efficiency of water splitting for hydrogen evolution on Rhodamine B sensitized P25 nanocomposites under visible light

The RhB-P25 nanocomposites synthesized by low temperature calcination were used for visible light induced photocatalytic water splitting. It was confirmed by X-ray diffraction (XRD) and field emission scanning electron microscope(FESEM)characterization that the crystalline phase and morphology of P25 catalyst were not changed by calcination treatment. UV-visible absorption spectra and FT-IR spectra indicated that there was a strong mutual interaction between RhB and P25. PL spectra also proved that electrons could easily transfer from RhB to P25 after the low temperature calcination treatment. The highest rate of hydrogen evolution was observed for the sample calcined at 250℃,about 65.1 μmol/(g·h) under visible light irradiation, which was 1.8 times larger than that of the physical mixture of P25 and RhB.