چكيده به لاتين
Abstract:
In this research, in the first stage, synthesis of cobalt ferrite nanoparticles (CoFe2O4) with green, low cost and fast procedure was considered. For this purpose, solvent free self-combustion with microwave assisted technique was used that is less reported and has the expected properties. In this method, the acetamid and glycine as fuel and the ammonium nitrate as oxidizing with different molar ratio were used. The use of copper oxide in the synthesis of cobalt ferrite was reported for the first time. The advantages of this technique is one-step synthesis without need of calcination, saving time, energy and consumption materials, low cost of raw materials, reproducibility, capability of industrialization, environmental friendly and no need of dangerous and poisonous solvents. In the second stage, for the first time, ferrite nanoparticles as the core and mixed metal oxides of bismuth tungstate and bismuth molybdate as the shell were used to prepare a core-shell structure by hydrothermal method. Also, to carry out the project, from TEOS as the bonding layer (linker) between the core and the shell layer was used. Since it is difficult to separate the metal oxides from aqueous solutions, so providing core- shell structures of these metal oxides with magnetic ferrite (the core) was considered. Also, increasing catalysis properties and preventing agglomeration of the magnetic particles were the other aim of the project. To characterize the products, different techniques of FT-IR, XRD, SEM, EDX, VSM, BET and TEM were used. At last, applications of synthesized bismuth tungstate and bismuth molybdate to form of the core-shell (with a magnetic core and silica intermediate layer) and synthesized bismuth tungstate and bismuth molybdate (without a magnetic core and silica intermediate layer), as a catalyst for photo degradation of organic dye pigments (Rh B) were analyized and compared.
Keywords: Cobalt ferrite, nanoparticles, core-shell structure, bismuth tungstate, bismuth molybdate, photo degradation.
