Characterization of NOx sensor using doped In2O3

To develop a highly sensitive gas sensor monitoring NO,, various kinds of n -type semiconductors made of In2O3 were prepared, and the relations between doped elements and gas sensitivities or response times were studied. Conse quently, it was found that the samples doped with less than 1 at.% alkali-e arth metal components have high sensitivities and responsiveness. The gas-a bsorbing phenomena were investigated using highly sensitive thermal analysi s. From the result, it was indicated that alkali-earth component-doped In2O 3 materials have higher adsorption ability of NOx than pure In2O3 has.