Synthesis, Characterization and Photocatalytic Performance of Poly-3-Thenoic Acid/Cu-TiO2 Nanohybrid for Efficient Visible Light Assisted Degradation of Bismarck Brown R

The present work reported on the synthesis and characterization of Poly-3-Thenoic acid/Cu-TiO2 nanohybrid (PCuT) for the photocatalytic degradation of organic azo dye pollutant from wastewater. The as-synthesized nanohybrid by an in-situ modified sol-gel method including chemical oxidative polymerization was characterized by X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, UV-visible diffuse reflectance spectroscopy (UV-vis.DRS), scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDX), transmission electron microscopy (TEM) and Brunauer-Emmet-Teller (BET) surface area analysis. The characterization results revealed the formation of small aggregates of polymer contained high crystalline anatase TiO2 nanoparticles (XRD) with narrowed bandgap energy (UV-vis.DRS), decreased particle size (TEM) with smooth surface morphology (SEM) and large surface area (BET). All the constituent elements of the polymer and Cu-TiO2 were found in the PCuT nanohybrid material (EDX) and their chemical interaction studied by FT-IR confirmed the stability of the nanohybrid. The photocatalytic activity of the nanohybrid was tested by the degradation of Bismarck Brown R dye under visible light irradiation. To enhance the photocatalytic efficiency, effects of various catalyst/dye reaction parameters such as polymer content, solution pH, catalyst dosage, and initial dye concentration were studied and optimized. HIGHLIGHTS Poly-3-Thenoic acid/Cu-TiO2 nanohybrid material was successfully synthesized by in situ modified sol-gel process Poly-3-Thenoic acid has enhanced the visible light absorption capacity of anatase TiO2 in nanohybrids Electron-hole recombination in TiO2 was effectively inhibited by Cu doping Bismark Brown R, an organic pollutant was successfully degraded in 75 min of visible light irradiation GRAPHICAL ABSTRACT

Preparation of TiO2 Nanotube Array on the Pure Titanium Surface by Anodization Method and Its Hydrophilicity

In this work, a highly ordered TiO2 nanotube array on pure titanium (Ti) was prepared by anodization. The effects of the applied voltage and anodization time on the microstructure of the TiO2 nanotube arrays were investigated, and their hydrophilicity was evaluated by the water contact angle measurement. It was found that a highly ordered array of TiO2 nanotubes can be formed on the surface of pure Ti by anodized under the applied voltage of 20 V and the anodization time in the range of 6-12 h, and the nanotube diameter and length can be regulated by anodization time. The as-prepared TiO2 nanotubes were in an amorphous structure. After annealing at 550°C for 3 h, the amorphous TiO2 can be transformed to the anatase TiO2 through crystallization. The anatase TiO2 array exhibited a greatly improved hydrophilicity, depending on the order degree of the array and the diameter of the nanotubes. The sample anodized at 20 V for 12 h and then annealed at 550°C for 3 h exhibited a superhydrophilicity due to its highly ordered anatase TiO2 nanotube array with a tube diameter of 103.5 nm.