Graphitic-C3N4 modified ZnAl-layered double hydroxides for enhanced photocatalytic removal of organic dye

摘要

Layered double hydroxides (LDH) are one of the most important photocatalyts intensively investigated for photodecolorization of organic dyes. ZnAI-LDH was successfully modified with graphitic-C3N4 (g-C3N4) by a simple in situ crystallization technique. The obtained C3N4/ZnAI-LDH composites were thoroughly characterized by Scanning electron microscopy (SEM), High-resolution transmission electron microscopy (HRTEM), powder Xray diffraction (XRD), X-ray photoelectron spectroscopy ()CPS), UV-Vis diffuse reflectance spectroscopy (DRS). The detailed analysis indicated that g-C3N4 sheets could act as substrate to induce the growth of LDH crystallites and ZnAl-LDH platelets randomly distributed on the sheets with a strong interaction between them. The photo catalytic activities of C3N4/ZnAl-LDH composites toward decolorization of methylene blue (MB) highly depended on the loading of g-C3N4. At the g-C3N4 weight loading of 18%, the rate constant of C3N4/ZnAI-LDH was more than five times and nearly two times than that of pure ZnAI-LDH and g-C3N4 respectively. The enhanced activity of C3N4/ZnAI-LDH composites could be ascribed to the synergistic effect between two components of the composites. (C) 2017 Elsevier B.V. All rights reserved.