تحضير وتوصيف المتراكب النانوي (/Al2O3 (MoFe2O4 كمحفز ضوئي لتكسير صبغة القرمزي النيلي

Preparation and Characterization of MoFe2O4 /Al2O3 Nanocomposites for Photocatlytic of Indigo Carmine Dye

ABSTRACT

This work consists of three main parts: The first part illustrates the synthesis of spinel Molybdenum Ferrite (MoFe2O4) nanoparticles, via the hydrothermal method using two types of surfactant: anionic is sodium dodecyl sulfate (SDS) and cationic is cetramide (CT) as a template and stabilizer. The Molybdenum Ferrite -Alumina (MoFe2O4/Al2O3) nanocomposites, was prepared by incorporating the spinel MoFe2O4 with synthesis Al2O3 by ultrasonic waves technique, which is a simple, fast, environmentally beneficial technique.
Part two includes the characterization of the prepared MoFe2O4, synthesis Al2O3, and their nanocomposites, using the techniques of FT-IR, XRD and SEM-EDX. The FT-IR spectra showed the tetrahedral and octahedral locations of molybdenum, and iron for all the catalysts prepared. The XRD analysis confirmed the spinel MoFe2O4, synthesis Al2O3, and thier nanocomposites are successfully prepared with nano-sizes. The mean crystal size for synthesis MoFe2O4 ¬ catalysts increase after incorporating with Al2O3¬¬. SEM analysis indicated the shape of prepared spinel MoFe2O4 in the presence of anionic SDS-surfactant, which found to be like-caviar, and its composite with Al2O3 is like-grains, while the shape of the spinel MoFe2O4 in the presence of cationic CT -surfactant and its composite with alumina are nanoplate and like-Popcorn nanoparticles, respectively. The shape of Al2O3 is ocurred like-brain cells. Based on EDX spectra, the elements Fe, Mo, Al, and O demonstrate. The band-gaps (Bg) determined using Tauc equation, the Bg ranges of all samples are proved their photocatalysts with ranged 2.78 eV to 4.44 eV.
The pH of point of zero charge(pHzpc) was determined for all samples using titration method under purged nitrogen, and found the ranged from 1.6 to 5.9.The pHzpc range of synthesis MoFe2O4 calatsts elevale after synthesis of composites. The quantum yields (Φ) of de-colorization IC dye with studied photocatalysts are found less than 1.
Part three focuses on the ability and evaluates the effectiveness of the MoFe2O4, Al2O3, and its nanocomposites on the de-colorization of indigo carmine IC dye. The effect of various factors on the photo decolorization of indigo carmine IC dye utilizing photocatalysts in the presence of SDS and CT surfactants were illustrated. Temperature and initial pH are two of these parameters. The best initial pH is occurred equal to 5.3.
The thermodynamic parameters were calculated using the Eyring-Polanyi equation, the equation of Arrhenius, and the Gibbs equation. The photoreactions with using MoFe2O4 in presence CT-surfactant and its composite are an exothermic, spontaneous reaction and less random. On the contrary, the photoreactions with using MoFe2O4 in presence SDS-surfactant is endothermic more random and nonspontinous, and its composite are an exothermic, spontaneous reaction and less .