The synthesis of cobalt nanoparticles by solution combustion synthesis method in a new reactor at low-temperature conditions

The novelty of the present paper was the construction of a new reactor to synthesize the cobalt nanoparticles (NPs) by solution combustion synthesis (SCS) method for reducing the processing temperature of cobalt production. To perform the SCS process, a reactor was designed and constructed and the synthesis process was performed using cobalt (II) nitrate-6-water as oxidizer along with glycine and urea as fuels. The effect of the molar ratio of glycine fuel to oxidizer and fuel type parameters on the purity of the products were examined. The XRD and FESEM analysis were used to characterize the obtained products. Based on FESEM analysis and the Scherrer equation, the mean size of all samples was under 100 nm and the reactor loaded with the glycine fuel provided the lowest particle sizes by around 14 nm and produced particles with better surface adhesion. It was found that the glycine fuel was determined the best fuel compared to urea because of producing temperatures near 400°C. Compared to traditional gas-solid reactions, the operating temperature of this process was under 400°C which was considerably lower than the operating temperature of gas-solid reactions occurred at temperatures higher than 800°C.