Gas sensing and structural properties of variously pretreated nanopowder tin (IV) oxide samples

The correlation between the gas sensing properties and the pore structure o f pure nanopowder SnO2 samples subjected to varying degrees of thermal pret reatment has been investigated. It is shown that both the intrinsic air res istance and the sensitivity to reducing gases are generally more dependent upon operating temperature than the degree of pretreatment. Nevertheless, t here is evidence for a correlation between the porosity and the observed ga s sensitivities of samples which have not undergone significant grain growt h. It is concluded that under fixed operating conditions, the pore structur e of the oxide strongly influences the observed gas sensitivity in such sam ples. (C) 1998 Elsevier Science S.A. All rights reserved.