English
 
Help Privacy Policy Disclaimer
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT
  X-ray Microspectroscopy and Ptychography on Nanoscale Structures in Rock Varnish

Förster, J.-D., Bykova, I., Macholdt, D. S., Jochum, K. P., Kappl, M., Kilcoyne, A. L. D., et al. (2021). X-ray Microspectroscopy and Ptychography on Nanoscale Structures in Rock Varnish. The Journal of Physical Chemistry C, 125. doi:10.1021/acs.jpcc.1c03600.

Item is

Files

show Files

Locators

show
hide
Description:
-
OA-Status:
Green

Creators

show
hide
 Creators:
Förster, Jan-David1, Author           
Bykova, Iuliia, Author
Macholdt, Dorothea S.2, Author           
Jochum, Klaus Peter2, Author           
Kappl, Michael, Author
Kilcoyne, A. L. David, Author
Müller, Maren, Author
Sorowka, Antje3, Author           
Weber, Bettina1, Author           
Weigand, Markus, Author
Schütz, Gisela, Author
Andreae, Meinrat O.1, Author           
Pöhlker, Christopher1, Author           
Affiliations:
1Multiphase Chemistry, Max Planck Institute for Chemistry, Max Planck Society, ou_1826290              
2Climate Geochemistry, Max Planck Institute for Chemistry, Max Planck Society, ou_2237635              
3Particle Chemistry, Max Planck Institute for Chemistry, Max Planck Society, ou_1826291              

Content

show
hide
Free keywords: -
 Abstract: X-ray microspectroscopy is a powerful analytical method in geoscientific and environmental research as it provides a unique combination of nanoscale imaging with high spectroscopic sensitivity at relatively low beam-related sample damage. In this study, “classical” scanning transmission soft X-ray microscopy (STXM) with X-ray absorption spectroscopy and the recently established soft X-ray ptychography are applied to the analysis of selected rock varnish samples from urban and arid desert environments. X-ray ptychography enhances the spatial resolution relative to STXM by up to 1 order of magnitude. With its high chemical sensitivity, it can resolve nanoscale differences in valence states of the key varnish elements manganese (Mn) and iron. Our results emphasize the complex nanoarchitecture of rock varnish as well as the diverse mineralogy of the Mn oxy–hydroxide matrix and its embedded dust grains. In contrast to the fast-growing urban varnish, the slow-growing arid desert varnish revealed a remarkable nanoscale stratification of alternating Mn valence states, providing hints on the layer-wise and still enigmatic growth process.

With “energy screening point scan spectra”—in short “ptychography E screening”—we refer to energy scans with an illumination spot diameter of about 100 μm at a fixed beam location on the sample. These scans were conducted prior to ptychography image stack scans in order to resolve the precise position of spectral features and to define the most appropriate energies for the ptychography images to achieve the best chemical contrast.

Details

show
hide
Language(s): eng - English
 Dates: 2021-10-06
 Publication Status: Published online
 Pages: 14
 Publishing info: -
 Table of Contents: -
 Rev. Type: Peer
 Identifiers: DOI: 10.1021/acs.jpcc.1c03600
 Degree: -

Event

show

Legal Case

show

Project information

show

Source 1

show
hide
Title: The Journal of Physical Chemistry C
  Abbreviation : J. Phys. Chem. C
Source Genre: Journal
 Creator(s):
Affiliations:
Publ. Info: Washington, D.C. : American Chemical Society
Pages: - Volume / Issue: 125 Sequence Number: - Start / End Page: - Identifier: ISSN: 1932-7447
CoNE: https://pure.mpg.de/cone/journals/resource/954926947766