Evolution and fractal growth of micro/nano structured wires of ruthenium synthesised by microwave irradiation of ruthenium dioxide

Ruthenium metal wires up to 3 mm long and 10–20 µm diameter, were produced in 20–30 s from anhydrous ruthenium dioxide by irradiation at 600 W in a microwave oven. The irradiation led to decomposition of ruthenium dioxide powder to ruthenium metal particles that sintered together along microwave field lines producing wires. Irradiation over 90 s produced larger features of metallic ruthenium with evidence of molten metal having been present. The evolution of wire growth proceeded in a fractal manner with self-similarity existing from the smallest to the largest wires.