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Ruptured tubular structured graphitic-carbon nitride (RT g-C3N4) was prepared, followed by in-situ growth of carbonate-intercalated ZnCr layered double hydroxide (LDH) on its surface by the co-precipitation method. The fabricated composites contain varying amounts of the LDH. An increase in the specific surface area of the g-C3N4/LDH3 composite (103.74 m2/g) was observed as compared to RT g-C3N4 (7.55 m2/g) and pristine LDH (11.26 m2/g). The formation, morphology and chemical composition of the pristine RT g-C3N4, pristine LDH and composites were examined by powdered-X-ray diffraction (p-XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), transmission electron microscopy (TEM), and Fourier transform infrared spectroscopy (FTIR) techniques. Optical measurements by ultraviolet-visible (UV) diffuse reflectance spectroscopy revealed that the band gap of the composites can be tuned by varying the LDH concentration in the composite. The ability towards the separation of photo-generated electron-hole pairs was examined by photoluminescence (PL) and the curves of transient photo-current with time. Mott-Schottky measurements were carried out to determine the flat band potential. Finally, the photoelectrocatalytic activity represented by measurements of transient photo-current with time (i-t curve), electrochemical impedance spectroscopy, and linear sweep voltammetry (i-v curve) was examined.

International audience; In this work, we report a novel photocatalyst based on boron and nitrogen co-doped TiO2 rutile (1 1 0) honeycomb structures. The photocatalyst has been prepared by simultaneously oxidizing and doping a Ti-foil substrate at 750 degrees C. The unit cell volume and the crystallite size of grown TiO2 films were measured by Rietveld refinement analysis. The co-doping by boron and nitrogen was achieved simultaneously with the oxidation of the titanium, resulting in a rutile (1 1 0) textured TiO2 film. X-ray photoelectron spectroscopy analysis revealed the presence of Ti-O-N and Ti-O-B-N bonds, and the presence of crystal defects in the lattice was detected and displayed by Raman spectroscopy. The water photo-oxidation properties have been measured as well, and the photocurrent of the B/N co-doped rutile sample prepared reached 270 mu A/cm(2) at 1 V under visible light and was stable in time. The efficient visible light absorption properties of the fabricated nanomaterial were attributed to the presence of oxygen vacancies and the introduction of impurity levels, as well as to synergistic effects between the introduced boron and nitrogen elements. The results presented demonstrate a new route for the preparation of TiO2 based catalysts, and open prospects for the photocatalysis community.