Fabrication of the composite nanofibers of NiO/γ-Al₂O₃ for potential application in photocatalysis

Composite nanofibers of NiO/γ-Al₂O₃ were fabricated by sol–gel processing and electrospinning followed by calcination of precursor composite fibers of nickel acetate/aluminum acetate/polyvinylpyrrolidone. Calcination at high temperatures allows for preservation of the NiO/γ-Al₂O₃ in fibrous form with a fineness of 322±69 nm in diameter. The composite fibers calcined at 800 or 1000 °C exhibited the nickel oxide and the γ-alumina phases, and higher calcination temperature was found to be in favor of crystalline development. EDS analysis confirmed that the Ni: Al ratio is about the same as the precursor formulation prepared for electrospinning. Finally, photocatalytic activity of the NiO/γ-Al₂O₃ nanofibers in comparison with TiO₂ nanoparticles was investigated by evaluating the photodegradation of hazardous dye Rhodamine B. It was found that the as-fabricated NiO/γ-Al₂O₃ composite nanofibers possessed a photocatalytic efficiency of 85.56%, which was nearly the same photocatalytic activity as the TiO₂ nanoparticles but can be recycled more easily. This work offers a direct insight into the comparison of photocatalysis of NiO/γ-Al₂O₃ nanofibers and TiO₂ nanoparticles and suggests the great potential of using the developed nanofibrous NiO/γ-Al₂O₃ for practical photocatalysis applications in various air/water pollution controls.