Tryptone based synthesis of TiO2@graphite carbon heterojunction with enhanced Photoreduction activity under visible light

Abstract Graphite carbon (GC)/TiO 2 composites were synthesized though a facile one-step thermal heating method. Degussa P25 TiO 2 was employed as main precursor and commercial available tryptone was used as pore-forming carbon source. X-ray diffraction, Raman spectroscopy, transmission electron microscopy, nitrogen adsorption-desorption analysis and X-ray photoelectron spectroscopy demonstrated the presence of a GC layer and a unique core@shell structure of TiO 2 /GC composites. The novel TiO 2 @GC catalysts, which possessed abundant mesopores, exhibited strong catalytic activities in Cr 6 + photoreduction under visible light irradiation. The TP-550 photocatalyst showed 7-fold higher activity compared with P25 TiO 2 , which can be ascribed to the formation of TiO 2 @GC heterojunction and its unique mesoporous structure.