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An investigation into the electrochemical reduction of tantalum pentoxide (Ta 2 O 5 ) to tantalum metal in molten calcium chloride was performed. The oxide was made the cathode, and either graphite or tin oxide rods were selected as the anodes. The experiments were terminated after 8 hours of potentiostatic electrolysis using a two-electrode setup, with the current and anodic potential recorded. The cathode products were analyzed by means of X-ray diffraction, scanning electron microscopy (SEM), and inert-gas fusion analysis. The key result is that tantalum can be produced using either anode, but the tin oxide anode leads to greater current efficiency and a cleaner melt with no significant differences in the product microstructure.

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Nanoparticles of Ca-Ru-O precursors have been prepared using a reverse micelle. Transmission electron microscopy and x-ray diffraction techniques showed that the precursors had an amorphous structure. The average diameter of the amorphous Ca-Ru-O particles was shown to be approximately 10 nm (within a range of +/- 2 nm). An interesting result was that a rod-like nano-CaRuO(3) perovskite was observed when the precursor was sintered at a temperature of 950 degrees C. Furthermore, the conversion of the powders to crystalline CaRuO(3) perovskite occurred upon heat treatment at 450 degrees C in air. This is much lower than that for a standard solid-state reaction for CaCO(3) and RuO(2).