The previously developed theory of sensor response is validated by detailed comparison with experiment. For this purpose, new experiments are performed to investigate the sensitivity of semiconductor tin dioxide (SnO 2 ) nanostructured thin films with average nanoparticle diameter ≈120 nm as a function of temperature and concentration of analyte hydrogen gas. Concurrently, the sensor properties are calculated at experimental conditions by taking into account the increase of surface chemical reactions with temperature as well as subsequent dominance of desorption over adsorption processes at high temperatures. Comparative analysis of temperature and nanoparticle size dependence of sensor response is also performed using experimental data from other groups. Qualitative agreement between experiment and theory is achieved.
A theory of sensor response to reducing gases in nanostructured semiconducting oxides was devel oped for the example of SnO 2 . Donor impurities (oxygen vacancies) provide noticeable electron density in the conduction band. Oxygen atoms, which appear in the adsorption of oxygen on the surface of oxide nano particles, are electron traps; they sharply decrease system conductivity. In the adsorption of reducing gases (H 2 , CO), oxygen atoms react with them, electrons are released, and conductivity increases; this is the sensor effect. A kinetic scheme corresponding to the picture described above was constructed, and the correspond ing equations were solved. As a result, the dependences of sensor sensitivity on temperature, hydrogen pres sure, and the mean size of oxide nanoparticles were obtained. The dependences satisfactorily described the literature experimental data.
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