Sol-gel synthesis of NiAL2O4 nanoparticles and study of their photocatalytic activity for the degradation of direct blue 129 dye

Materials at the nanometer scale have been studied for decades because of their unique properties arising from the large fraction of atoms residing on the surface, and also from the finite number of atoms in each crystalline core. Especially, because of the increasing need for high are a density storage, the synthesis and characterization of semiconductor nanocrystals have been extensively investigated [1,2]. The search for low cost and efficient photocatalysts is still continuing. Some spinel-type oxides such as NiAl2O4, ZnAl2O4 and CuAl2O4 used as photocatalysts are semiconductor materials with narrow band high and these materials have been proven to be an efficient in the degradation of pollutants and/or the production of photo-catalytic hydrogen [3-6]. Among the many types of oxide spinel materials، NiAL2O4 show a high catalytic property. In addition، nickel aluminate has a high thermal stability، high mechanical resistance، hydrophobicity and low surface acidity [7]. In this work, we have reported the synthesis of NiAL2O4 aluminate spinel nanoparticles (NPs) using sol-gel method and its photocatalytic dye degradation ability from aqueous solution were investigated. This method has various advantage such as nontoxic, economic viability, ease of scaling up, less time consuming and environmental friendly approach for the synthesis of NiAL2O4 NPs without using any organic chemicals. The synthesized nanoparticles were characterized by energy dispersive X-ray analysis (EDX), powder X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), Fourier transforms infrared spectroscopy (FTIR) and percent of dye degradation which was followed by UV–Visible spectroscopy. The effects of process parameters like, catalyst dosage, initial dye concentration, and visible light irradiation on dye degradation have been studied. The current photocatalyst exhibited notable catalytic activity for the degradation of direct blue 129 in water under visible light irradiation. This result suggests that as-obtained nanocrystalline nickel aluminate as favorable material has high potential to be used for photocatalytic applications under visible light.