NANOSIZE NIO YSZ POWDERS PRODUCED BY ICP TECHNIQUE/

The plasma synthesis of nanosize NiO/ZrO2 and NiO/YSZ powders has been developed by introducing a mixture of coarse-grained zirconia, yttria and nickel oxide into an inductively coupled plasma flame. The averag e particle size of the prepared powder is in the range of 16-55 nm and specific surface al ea is 15-35 m(2) g(-1). The phase and granulometr ic composition of the powders produced depend on reagent concentration in the plasma flame and cooling rate, on the content of Y2O3 and NiO. In the NiO/ZrO2 system NiO increases the fraction of the metastable t etragonal phase of ZrO2 but in the NiO/YSZ system promotes formation o f non-transformable t'-phase and cubic ZrO2. (C) 1997 Elsevier Science Limited.