Skip to main content

Incorporation of Aluminum into C–S–H Structures: From Synthesis to Nanostructural Characterization

Buy Article:

$51.00 plus tax (Refund Policy)


C–A–S–H (C=CaO, A=Al2O3, S=SiO2, H=H2O in cement nomenclature) phases have been synthesized from CaO, SiO2, and AlNaO2. The initial CaO/SiO2 (C/Sinitial) ratios varied from 0.8 to 1.5 and the initial Al2O3/SiO2 (A/Sinitial) ratio was set to 0.1. Samples were characterized by X-ray diffraction and chemical analyses of their equilibrium solutions. This paper describes experiments using a low-voltage scanning transmission electron microscopy (STEM-in-SEM) imaging system that allows transmission observations in an environmental scanning electron microscope. Observations of the nanostructure were also performed by transmission electron microscopy (TEM). Two types of morphologies were clearly observed: fine fibrillar aggregates and small plates, the latter being particularly sensitive to beam damage. Despite their different appearance, both of these phases were amorphous, and the small plates were richer in aluminum. The fraction of the small plate phase increased with the C/Sinitial ratio. TEM interpretations showed that C–A–S–H phases were not stable under the electron beam and high-magnification observations could significantly modify their structure. Images and chemical analyses acquired with STEM-in-SEM appeared as valuable sources of information because they offered a large observation field comparable to a transmission electron microscope and better magnification resolution than a classical scanning electron microscope.

Document Type: Research Article


Affiliations: 1: CEA Valrhô, DEN/MAR/DTCD/SPDE/L2ED, 30207 Bagnols-sur-Cèze cedex, France 2: MATEIS, INSA-Lyon, CNRS UMR 5510, F-69621, France

Publication date: 2008-07-01

  • Access Key
  • Free content
  • Partial Free content
  • New content
  • Open access content
  • Partial Open access content
  • Subscribed content
  • Partial Subscribed content
  • Free trial content
Cookie Policy
Cookie Policy
Ingenta Connect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more