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Abstract Doped cerium oxide (CeO 2 ) based electrolytes are attractive alternative materials to replace the existing yttria-stabilized zirconia (YSZ) used as electrolyte for SOFC (solid oxide fuel cells). Cerium oxide electrolytes offer a similar performance to YSZ electrolytes at a lower cell operating temperature (~600--800 ° C), therefore reducing thermal stresses and solid state reactions among the cell components.Doped Ce 1-x Me x O 2-x/2 (Me = Gd, Sm or Y) fine \hbox{powders} were synthesized from nitrate salts dissolved in water using a radio frequency inductively coupled plasma reactor. It was demonstrated that the relative concentrations of Ce and dopants fed in the solutions were retained in the synthesized powders. The products were all nano-crystalline with the basic crystal structure of CeO 2 and the crystal size of the products was essentially independent of the dopant used. The particle size distributions obtained were multimodal and in most cases trimodal. The results obtained differ from a previously reported mechanism of particle synthesis from liquid precursors.

A stable TiCl4 plasma was produced using a simplified d.c. torch. The arc was struck between two concentric ring electrodes, d mm apart, and rotated using a magnetic coil. The electrode material was a new TaC composite. The arc was operated at 100 A for up to I h using plasma gas containing 0–30% TiCl4. The voltage was 24–60 V, depending on the TiCl4 concentration. The electrode erosion rate was of the order of 20µg/C. It is shown that the erosion rate is a function of the aerodynamic drag of the are column.