Semi-Empirical and Ab Initio Studies of Low-Temperature Adsorption of Oxygen and CO at (110) Face of SnO2
Research output: Contribution to journal › Article › Scientific › peer-review
|Number of pages||6|
|Journal||IEEE Sensors Journal|
|Publication status||Published - 2002|
|Publication type||A1 Journal article-refereed|
Using a first principles electronic structure calculation method based on the density functional theory (DFT), and also using a semi-empirical (PM3) method, surfaces of the (110) face of SnO2 with and without CO and oxygen adsorbates have been studied. For semi-empirical and DFT calculations, cluster models and the slab models were constructed, respectively. It was found that oxygen adatoms on a perfect stoichiometric (110) surface do not form without precursor for O2 dissociation. The chemisorbed atomic oxygens are metastable, but may stabilize in the form of carbon-related complexes in CO environment, which is enhanced by the energy barrier for CO2 formation. It is energetically favorable for CO to form structures like oxalate and bidentate carbonate. It is proposed that, in a low-temperature range, chemisorption processes may contribute to the sensitivity of SnO2 film. © 2002 IEEE.