Iranian Journal of Materials Science and Engineering

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A series of MAl₂O₄ (M=Ni, Zn, and Cu) aluminates were prepared by using impregnation method; the metal content of the products was ranged between 5wt% to 25wt%. The samples were characterized by x-ray diffraction (XRD), Brunauer Emmett Teller (BET) surface area, NH₃ temperature-programmed desorption (NH₃-TPD), and inductively coupled argon plasma (ICP).

The specific surface areas of zinc, nickel and copper aluminates were in the ranges of 47-77m²/g, 63-87m²/g and 1.6-3m²/g, respectively. The surface acidity decreased in the order of CuAl₂O₄<< NiAl₂O₄< ZnAl₂O₄<< Al₂O₃. By increasing the amount of metals in the samples, the number of acidic sites decreased, but their strength did not significantly change. Ni-aluminates have fewer acidic sites than Zn-aluminates, particularly in strong acid sites

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In this research, using impregnation method, spinel cobalt and copper ferrites nanoparticles are synthesized on the surface of hematite. Synthesized powders were characterized and examined by FTIR, XRF, XRD, FESEM, BET and EDS analysis and the dye degradation were investigated by UV-vis and AAS methods. Specific surface area increased especially in the sample containing cobalt, which indicates the precise of synthesis and the creation of high surface nano particles at hematite surface. The size of particles was in the nano scale and a good uniformity observed in the structure. The results indicated a significant increase in the catalytic ability of hematite nano composite after synthesis. Their catalytic capability investigated by the Fenton reaction with complete removal of methylene blue from the solution via UV-vis irradiation. The samples stability discovered to be excellent by the AAS method.