Microwave hydrothermal flash synthesis of nanocomposites Fe-Co alloy/cobalt ferrite

The present article presents, for the first time, the last developments reported for an original microwave hydrothermal flash synthesis of Fe-Co alloys (FeyCo1-y)/cobalt ferrite (Fe3-xCoxO4)nanocomposites. Synthesis was performed in alcoholic solutions of ferrous chloride, cobalt chloride and sodium ethoxide (EtONa) using a microwave autoclave (The RAMO system) specially designed by authors. Compared with conventional synthesis, smaller grains (100 nm compared to 1 mum) can be produced in a short period (e.g. 10s) using a less basic medium. In all the cases, the microstructure and the amount of metal inside the composite particles are very different from the product obtained via a classical route. Indeed, 20% of metal was routinely obtained using the microwave flash synthesis. Nevertheless, this mean of production is more efficient and much faster than the ones commonly used to produce this type of nanocomposites. (C) 2004 Elsevier Inc. All rights reserved.