A New Model of Thermal Desorption of Nitrogen from a Nonhomogeneous Catalyst Surface
Tóm tắt
A new mathematical model is proposed for temperature recombination of atomic nitrogen on the (111) face of the iridium single crystal and on iridium foil, allowing for geometrical nonhomogeneity of the catalyst surface. The model describes the main qualitative features of laboratory experiments: the effect of the catalyst surface structure and the adsorbed oxygen on nitrogen thermal desorption spectra. Conditions are determined when an additional low-temperature peak appears in the N2 thermal desorption spectrum. The results are compared with calculations using traditional models of associative thermal desorption from homogeneous surfaces, including models that allow for lateral interactions in the adsorption layer. The numerical analysis is carried out using deterministic and stochastic approaches.
Tài liệu tham khảo
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