The method for synthesizing metal oxide nanopowder produces powders of
nanoparticle size from metals having relatively low boiling temperatures,
such as zinc, tellurium, bismuth, and strontium by vapor-phase oxidation
using a conventional 2.45 GHz microwave oven. The energy that initiates
the combustion comes from the microwave through a susceptor tube that
absorbs radiant microwave energy and transfers it to the metal, which
evaporates to small particles inside the susceptor tube and then combusts
in air to form nanosize powder. The susceptor is made of silicon carbide
composite material.