Tungsten oxide nanoparticles grown by condensation in gas using domestic appliances

摘要

We report on the preparation of WO_3 nanostructures using tungsten wire and iron wool in a domestic microwave oven. Pure WO_3 nanoparticles were octahedral or rhombohedral while iron containing nanoparticles were spheroidal. Nanoparticles of monoclinic and cubic WO_3 were found in the interior of burned commercial light bulbs, where they grow by a spontaneous reactive gas condensation process. This process was emulated heating a W filament under N_2 inside a glass bell jar with a small air leak.