Fabrication of high-activity hybrid NiTiO3/g-C3N4 heterostructured photocatalysts for water splitting to enhanced hydrogen production

Novel NiTiO3/g-C3N4 hybrid photocatalysts were designed and fabricated for photocatalytic water splitting by harvesting solar energy. The as-prepared photocatalysts were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectra (XPS), ultraviolet visible diffuse reflection spectroscopy (DRS), photoluminescence spectroscopy (PL) and electrochemical impedance spectroscopy (EIS). The hydrogen evolution rate under visible light irradiation was measured in triethanolamine aqueous solution and NiTiO3/g-C3N4 hybrids demonstrate a much higher photo catalytic activity than pure g-C3N4 particles. Furthermore, it was observed that the rod-like NiTiO3 coupled with g-C3N4 showed better performance than the bulk flocculent NiTiO3 coupled with g-C3N4. When the content of rod-like NiTiO3 in NiTiO3/g-C3N4 hybrid catalysts was 3 wt%, the catalysts exhibited optimal activity, the rate of hydrogen generation was about 3 folds that of pure g-C3N4. The enhanced photocatalytic performance could be attributed to the strong light absorption in the visible region and the low recombination rate of photogenerated electrons and holes. (C) 2016 Elsevier Ltd and Techna Group S.r.l. All rights reserved.