Incorporation of Monovalent Cations in Sulfate Green Rust

Green rust is a naturally occurring layered mixed-valent ferrous–ferric hydroxide, which can react with a range of redox-active compounds. Sulfate-bearing green rust is generally thought to have interlayers composed of sulfate and water. Here, we provide evidence that the interlayers also contain mo...

Full description

Saved in:
Bibliographic Details
Published in:Inorganic chemistry 2014-09, Vol.53 (17), p.8887-8894
Main Authors: Christiansen, B. C, Dideriksen, K, Katz, A, Nedel, S, Bovet, N, Sørensen, H. O, Frandsen, C, Gundlach, C, Andersson, M. P, Stipp, S. L. S
Format: Article
Language:English
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Green rust is a naturally occurring layered mixed-valent ferrous–ferric hydroxide, which can react with a range of redox-active compounds. Sulfate-bearing green rust is generally thought to have interlayers composed of sulfate and water. Here, we provide evidence that the interlayers also contain monovalent cations, using X-ray photoelectron spectroscopy and synchrotron X-ray scattering. For material synthesized with Na+, K+, Rb+, or Cs+, interlayer thickness derived from basal plane spacings correlates with the radius of the monovalent cation. In addition, sequential washing of the materials with water showed that Na+ and K+ were structurally fixed in the interlayer, whereas Rb+ and Cs+ could be removed, resulting in a decrease in the basal layer spacing. The incorporation of cations in the interlayer opens up new possibilities for the use of sulfate green rust for exchange reactions with both anions and cations: e.g., radioactive Cs.
ISSN:0020-1669
1520-510X
DOI:10.1021/ic500495a