Chemical imaging of single catalyst particles with scanning μ-XANES-CT and μ-XRF-CTElectronic supplementary information (ESI) available. See DOI: 10.1039/c4cp04488f
The physicochemical state of a catalyst is a key factor in determining both activity and selectivity; however these materials are often not structurally or compositionally homogeneous. Here we report on the 3-dimensional imaging of an industrial catalyst, Mo-promoted colloidal Pt supported on carbon...
Saved in:
Main Authors | , , , , , , , , |
---|---|
Format | Journal Article |
Language | English |
Published |
03.12.2014
|
Online Access | Get full text |
Cover
Loading…
Summary: | The physicochemical state of a catalyst is a key factor in determining both activity and selectivity; however these materials are often not structurally or compositionally homogeneous. Here we report on the 3-dimensional imaging of an industrial catalyst, Mo-promoted colloidal Pt supported on carbon. The distribution of both the active Pt species and Mo promoter have been mapped over a single particle of catalyst using microfocus X-ray fluorescence computed tomography. X-ray absorption near edge spectroscopy (XANES) and extended X-ray absorption fine structure revealed a mixed local coordination environment, including the presence of both metallic Pt clusters and Pt chloride species, but also no direct interaction between the catalyst and Mo promoter. We also report on the benefits of scanning μ-XANES computed tomography for chemical imaging, allowing for 2- and 3-dimensional mapping of the local electronic and geometric environment, in this instance for both the Pt catalyst and Mo promoter throughout the catalyst particle.
Representative Pt L
3
edge XANES spectrum and sample reconstructed fluorescence maps during a XANES tomography experiment. |
---|---|
Bibliography: | 10.1039/c4cp04488f Electronic supplementary information (ESI) available. See DOI |
ISSN: | 1463-9076 1463-9084 |
DOI: | 10.1039/c4cp04488f |