At the first step CoFe2O4 nanoparticles were prepared via precipitation method and at the second step CoFe2O4–SnO2 nanocomposites were synthesized by a fast sono-chemical method. The prepared products were characterized by X-ray diffraction, scanning electron microscopy, and Fourier transform infrared spectroscopy. Magnetic property studies of the products were carried out using an alternating gradient force magnetometer and the results illustrated either ferromagnetic or super-paramagnetic behaviour of CoFe2O4 nanoparticles. The photocatalytic behaviour of CoFe2O4–SnO2 nanocomposites was evaluated using the degradation of four various azo dyes under ultraviolet light irradiation. The results show these nanocomposites have applicable magnetic and photocatalytic performance
