Sensor response and electron distribution in the systems of In2O3 nanoparticles decorated with CeO2 nanoclusters

Abstract

The charge distribution and spillover of oxygen atoms in nanostructured CeO2-In2O3 systems have been studied. The interaction of nanoobjects (nanoparticles or nanoclusters) i.e. the spillover of oxygen atoms from catalytically active CeO2 nanoclusters to In2O3 nanoparticles, results in an increase in the inhomogeneity of the radial electron density distribution in the nanoparticles. This in turn increases the resistance of the CeO2-In2O3 system in air relative to pure In2O3. It is shown here that the spillover of oxygen atoms in the two-component system (CeO2-In2O3) causes a shift of the maximum in the temperature dependence of the sensor response to hydrogen towards lower temperatures and a significant enhancement of the sensor response compared to one-component system (In2O3). The theoretical model developed agrees well with the published experimental data on the sensor response in In2O3 and CeO2-In2O3 systems.