Synthesis of mesoporous worm-like ZrO2-TiO2 monoliths and their photocatalytic applications towards organic dye degradation

The current article reports on the synthesis of a thermally stable mesoporous worm-like ZrO2 doped TiO2 monolith materials through a neutral templating route. The controlled thermal treatment facilitates clean removal of organic templates, resulting in,a stable and well-defined porous framework. The ZrO2 doped TiO2 monoliths serve as an efficient and reusable photocatalyst materials for the photodegradation of Naphthol Green B (NG-B), a widely employed organic dye stain, within 10 min of irradiation time frame. The synthesized monoliths are characterized using techniques such as X-ray diffraction (XRD), Xray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray (EDAX) spectroscopy, selected area electron diffractometry (SAED), UV-vis diffuse reflectance spectrophotometry (UV-vis-DRS), Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), photoluminescence spectroscopy (PLS), and Brunauer-Emmett-Teller (BET) adsorption isotherm. The XRD analysis confirms the retention of anatase phase by the ZrO2 doped TiO2 monoliths and also the mesoporous structure. The DRS and PLS analysis indicate that the ZrO2 doped TiO2 monoliths exhibit band gap narrowing in comparison to pure TiO2 monoliths, with improved quantum yield and photocatalytic efficiency. The BET analysis reveals a surface area and pore volume value of 80.2 m(2)/g and 8.1 nm, respectively, for ZrO2-TiO2 monolith materials. We have also investigated on the influence of solution pH, dye concentration, dopant stoichiometry, photocatalyst dosage and photo-additives on the photocatalysis process. (C) 2017 Elsevier B.V. All rights reserved.