core-shell structure

The construction and investigation of the properties of the molecular imprinting polymer (MIP) adsorbent to remove the copper ion pollutant from the aqueous environment was carried out in this research. In the first stage, iron/silica core-shell nanoparticles were made by co-precipitation method, and then functionalization and in-situ polymerization were done with monomer and target ion (copper), and finally, by washing the copper ion, the molecular imprinting polymer adsorbent was obtained. FTIR, XRD, TEM, FESEM, EDX, BET and VSM tests were performed to determine the absorbent properties. The results showed that the formation of the core-shell structure for iron/silica nanoparticles was successfully established and then the spherical structure of the polymer absorbent with an average particle size of about 30-40 nm was well formed. The results of the absorption tests for copper ion showed that the optimum amount of adsorbent dose is about 18 mg and the best amount of absorption occurs at a pH of about 7. High adsorption capacity, good selectivity and reusability for molecular role polymer adsorbent were observed in adsorption tests. The results of the adsorption-desorption tests showed that after 6 reuses of the adsorbent, a slight decrease (about 8%) in the adsorption removal occurred. To verify the adsorption performance, the synthesized adsorbent was placed in contact with a power plant water sample and showed an adsorption rate of 88% for copper ions.

In this study, nanocomposites with core-shell structure consisting of nickel ferrite and zinc sulfide were fabricated by rapid chemical method with the aim of enhancing the photocatalytic properties and were investigated in the ultraviolet region. Therefore, first samples containing nickel ferrite nanoparticles (NiFe2O4) were synthesized by co-precipitation method, then NiFe2O4-Zns nanocomposite with average diameters of 66 nm was made. The morphology and microstructure of the nanocomposites produced were investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). XRD analyzes show that the constructed nanostructures have a structure with a crystalline dominant phase. The magnetic properties of nanoparticles and nanocomposites prepared at room temperature were investigated using an alternating force gradient magnetometer (AGFM). The sample of nanocomposites produced using ultraviolet-visible (UV-Vis) optical spectrometer and the effect of the amount of adsorbent and irradiation time on the percentage reduction of dye concentration of solutions were investigated. The aqueous and methyl orange acids tested in the presence of the nanocomposite were significantly reduced, which is confirmed by the photocatalytic properties of the nanocomposite, which ultimately led to a reduction in the concentration of dyes used.

In the present research, nanoparticles and silicon nanoparticles were synthesized using gold catalyst by chemical vapor deposition methods and liquid-solid vapor VLS techniques at different times. The Nano structural properties of the synthesized samples were investigated using experimental techniques of scanning electron microscopy SEM, transmission electron microscopy TEM and X-ray diffraction XRD. The results of SEM images showed nanoparticles with spherical morphology with diameters in the range of 60 to 180 nm and nanoparticles with needle morphology. XRD analysis confirmed the presence of crystalline phase silicon peaks in the synthesized sample. The results of TEM and Raman show the inner structure of the samples at 10 and 20 nm scales as crystalline core-shell, respectively.