NO adsorption study on the distribution of Ni2 + ions on the various micro-environments of carriers
Tóm tắt
The decrease of the electron density in the d orbits of Ni2 + ions, resulting from the disturbance of micro-environments in which Ni2+ ions are located, makes the frequency of adsorbed NO shlft higher. The shift degree is determined mainly by the property of the microenvironments. When Ni2+ ions are located onSII,SII(SI) sites of Y zeolite or on the surface of γ-alumina, their NO adsorption gives rise to IR bands at 1 905, 1 900 and 1 855–1 875 cm−1, respectively. The distribution of Ni2+ ions on the various micro-environments of USY zeolite, Al2O3 and MS mixed carrier has also been discussed according to the different frequencies of adsorbed NO, as well as the influence of NiO loading.
Tài liệu tham khảo
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