Investigating the Synthesis agents of layered double hydroxides-iron Composite by Chemical Method to eva‎luate structural and magnetic properties

9/28/2023 12:00:00 AM

Layered double hydroxides are a group of anionic clays with physical and chemical properties similar to hydrous talc clay mineral. This category of materials, in recent years, due to their prominent features including; The ability to insert different molecules and anions in the interlayer space, layered structure, porosity and high specific surface in various fields have attracted the attention of scientists. In this research, magnetic nanoparticles of zero-valent iron coated with silica were synthesized by liquid phase reduction method, and after that, magnetic nanocomposite - double layer hydroxides were prepared by three methods: hydrothermal, ultrasonic and co-precipitation. Phase eva‎luation of the samples was done with the help of X-ray Diffraction (XRD) analysis, and then using Fourier transform infrared spectroscopy (FTIR), bonds were identified.Field emission scanning electron microscope (FE-SEM) images to study morphology and size distribution, vibrating sample magnetometer (VSM) to investigate magnetic properties and magnetization parameters, nitrogen adsorption and desorption (BET) to investigate specific surface area, size and type of porosity were done. Hydrothermal method, despite the formation of LDH layered structure, zero valence iron has been oxidized and transformed into magnetite and maghemite. By examining the effective parameters in the synthesis of layered double hydroxides, we found the optimal conditions of temperature ◦C40, time 14 hours and pH=10-9. According to the results of VSM analysis, the saturation magnetization for the ultrasonic sample is 26.6 emu/g and for the three samples obtained from the co-precipitation process in 8 hours, the room temperature and ◦C40 are 22.25 emu/g, 15/07 and 10/05 respectively. Considering the necessary conditions for the growth and crystallinity of the LDH shell, the results of BET analysis for the ultrasonic sample and co-precipitation at 40°C are equal to 73.708 and 87.537 m2/g, respectively which shows the effect of temperature and time on the growth and crystallinity of layered double hydroxides.

هيدروكسيدهاي دوتايي لايه اي , آهن صفرظرفيتي , نانوكامپوزيت هسته- پوسته هيدروكسيدهاي دوتايي لايهاي

Layered double hydroxides , zero valent iron , Core-shell nanocomposite of layered double hydroxides

Mohadese Aminian

Hajar Ghanbari