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Adsorption of SF₆ Decomposed Products over ZnO(1010): Effects of O and Zn Vacancies.

ABSTRACT: We carried out a density functional theory study to investigate the adsorption behavior of four kinds of SF₆ decomposed products over the ZnO(101̅0) surface. The effects of O and Zn vacancies on the surface were also considered. For perfect ZnO(101̅0) surface, the adsorption of SO₂ and H₂S exhibits stronger chemical interactions compared to the adsorption of SOF₂ and SO₂F₂. For SO₂ and H₂S adsorption, there may exist new chemical bond formation between the molecule and the surface and the H₂S molecule experiences one H-S broken bond. The introduction of O vacancy cannot obviously enhance the chemical interactions between these four molecules and the surface. However, the Zn vacancy on the surface can significantly elevate the chemical interactions between SO₂/H₂S and the surface. The two-coordinated O atom (O_2c) on the surface plays an important role. For SO₂ and H₂S adsorption, the S atom in SO₂ or H₂S tends to bond to the O_2c atom, bringing much larger adsorption energy compared to the adsorption over the perfect ZnO(101̅0) surface. This work can provide a basis for surface modification of ZnO in applications to detecting SF₆ decomposed products by theoretical evaluation.

SUBMITTER: Chen D

PROVIDER: S-EPMC6643918 | biostudies-literature |

REPOSITORIES: biostudies-literature

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