Presence Of TiO2 NPs Research Articles

Preparation of PVDF–TiO2 mixed-matrix membrane and its evaluation on dye adsorption and UV-cleaning properties

In this study, the polyvinylidene fluoride (PVDF)–Titanium dioxide (TiO2) mixed-matrix membranes were prepared via phase inversion technique. The properties of PVDF–TiO2 mixed-matrix membranes were characterized based on pore size distribution, membrane porosity, field emission scanning electron microscope (FESEM) and photocatalytic behavior. The hydrophilicity of the mixed-matrix membrane was enhanced and resulted in the improved pure water permeability (392.81±10.93l/m2hbar) compared to that 76.99±4.87l/m2hbar of the neat membrane. The neat and mixed-matrix membranes were further investigated in terms of filtration, adsorption and UV-cleaning properties based on methylene blue (MB) solution. Mixed-matrix membranes showed excellent removal efficiency (∼99%) when sodium dodecyl sulfate (SDS) was introduced into the MB feed solution. The produced mixed-matrix membrane shows some slight photocatalytic properties improvement as FTIR results reviewed that the cleavage of CN bonding due to MB adsorption reduced more significantly with the presence of TiO2 NPs and ultraviolet (UV) light irradiation. The UV-cleaning properties of the mixed-matrix membrane were further proved by the 100% flux recovery ratios (FRRs) for mixed-matrix membrane, suggesting that the embedded TiO2 NPs was photocatalytically active and able to degrade the adsorbed MB in the membrane.

Synthesis, characterization, and photocatalytic properties of ZnO nano-flower containing TiO2 NPs

In this study, TiO2-impregnated ZnO nano-flowers were synthesized by one-pot hydrothermal process. Aqueous suspension containing ZnO precursor and commercial TiO2 NPs (P25) is heated at 140°C for 2h. The morphology and structure of as-synthesized particles were characterized by field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), and X-ray diffraction (XRD), which revealed that TiO2 NPs were attached on the surface of ZnO flower. It was observed that the presence of TiO2 NPs in the hydrothermal solution could sufficiently decrease the size of ZnO flower. The hybrid nanostructure, with unique morphology, obtained from this convenient method (low temperature, less time, and less number of reagents) was found to be effective photocatalyst under UV-irradiation.