Structure of copper sites in zeolites examined by Fourier and wavelet transform analysis of EXAFS.

ABSTRACT: Copper-exchanged zeolites are a class of redox-active materials that find application in the selective catalytic reduction of exhaust gases of diesel vehicles and, more recently, the selective oxidation of methane to methanol. However, the structure of the active copper-oxo species present in zeolites under oxidative environments is still a subject of debate. Herein, we make a comprehensive study of copper species in copper-exchanged zeolites with MOR, MFI, BEA, and FAU frameworks and for different Si/Al ratios and copper loadings using X-ray absorption spectroscopy. Only obtaining high quality EXAFS data, collected at large k-values and measured under cryogenic conditions, in combination with wavelet transform analysis enables the discrimination between the copper-oxo species havin

SUBMITTER: Sushkevich VL 

PROVIDER: S-EPMC8159279 | biostudies-literature | 2020 May

REPOSITORIES: biostudies-literature