Production of cobalt and nickel nanoparticles

Cobalt and nickel nanoparticles find applications as catalysts, ceramic composites, magneto rheological devices and printed memory. Various production methods such as flame synthesis, spray pyrolysis, sol-gel and chemical vapour synthesis have been demonstrated in both gas and liquid phases. In liquid methods, multiple steps are required and impurities are more likely to occur than in gas-phase processes.

Chemical vapour is synthesised from vaporized cobalt chloride precursor occurs at a reaction temperature of 850-950°C. Here surface reaction dominates gas phase reaction and vapour pressure of cobalt or nickel chloride are high at the reaction temperature. During the process the flow is saturated with cobalt or nickel chloride by evaporating precursor powder from porous aluminium oxide pellets. The precursor powder is fed continuously to the reactor and in the reaction part hydrogen is mixed to nitrogen flow. The reaction is observed with FTIR. These nanoparticles can find applications in labelling biological analytes, high inductance low loss antennas, nanostructured ceramic composites, biosensors and in printed memory. The method is very cost effective as the precursor powder and carrier gases are inexpensive.