An efficient method for the preparation of magnetic Co3O4 nanoparticles and the study of their catalytic application
Hakimeh Ardeshirfard, Dawood Elhamifar
Abstract
In this study, magnetic cobalt oxide (Co 3 O 4 ) nanoparticles (NPs) were synthesized through a new and green method using cobalt chloride hexahydrate (CoCl 2 .6H 2 O), pluronic P123 as a stabilizer, and sodium borohydride (NaBH 4 ). The CO 3 O 4 nanoparticles were characterized by diffuse reflectance infrared Fourier transform spectroscopy, powder X-ray diffraction, X-ray photoelectron spectroscopy, energy-dispersive X-ray spectroscopy, scanning electron microscopy, and vibrating sample magnetometer. The magnetic Co 3 O 4 NPs were used as a catalyst with high activity and stability in the synthesis of tetrahydrobenzo[b]pyran derivatives. This reaction was carried out in water, as it is an environmentally friendly solvent, using a low loading of Co 3 O 4 NPs at room temperature. Various derivatives of aldehydes were used as substrates to obtain a high yield of the corresponding tetrahydrobenzo[b]pyrans in short times. In addition, the catalyst was recovered and reused several times with no notable decrease in its activity.