Nanoparticulate WO(3) films were prepared using microwave plasma synthesis and studied with respect to the electrical conductivity in dependence of ambient conditions. The WO(3) films with a monoclinic structure were made from cluster-assembled nanoparticles (diameter 3 nm) by means of dispersion and spin-coating. Above 100 °C a thermally activated decrease of the electrical resistance due to oxygen vacancy donors is found. A reversible increase of the electrical resistance R due to oxygen uptake is observed. The decrease of R in response to reducing H(2)S in the ppm range is studied in dependence of temperature and pre-annealing conditions.
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