Magnetic nanoparticles modified with layered double hydroxide (Fe₃O₄/C/CoFe-LDH) as an extremely effective catalyst in the construction of polyhydroquinolines

In this research, a modified magnetic nanocomposite based on layered double hydroxide (Fe₃O₄/C/CoFe-LDH) was synthesized through co-precipitation and thermal processes. Modification of the magnetic nanoparticles was carried out by applying a carbon coating. After the surface modification of these nanoparticles, LDH was immobilized on the surface of Fe₃O₄/C. To synthesize CoFe-LDH, a co-precipitation process was performed using cobalt (II) nitrate and iron (III) nitrate. The synthesized nanocomposite was characterized by FT-IR, XRD, SEM, EDS, STA, TEM, VSM and BET. After identifying of Fe₃O₄/C/CoFe-LDH, its catalytic activity in the Hantzsch reaction was evaluated. The investigations exhibited that in the presence of the designed catalyst, the expected products can be produced with a high yield in a very short time. In addition, the recyclability and reusability of the prepared nanocomposite were evaluated. The results of these investigations show that after four cycles, the recycled catalyst still maintains its activity and only causes a slight decrease in the reaction efficiency.