Next Article in Journal
Investigation of γ-(2,3-Epoxypropoxy)propyltrimethoxy Silane Surface Modified Layered Double Hydroxides Improving UV Ageing Resistance of Asphalt
Previous Article in Journal
On the Selective Laser Melting (SLM) of the AlSi10Mg Alloy: Process, Microstructure, and Mechanical Properties
Open AccessArticle

XPS Study on the Stability and Transformation of Hydrate and Carbonate Phases within MgO Systems

1
Berkeley Education Alliance for Research in Singapore, Singapore 138602, Singapore
2
Department of Civil and Environmental Engineering, Nanyang Technical University, Singapore 639798, Singapore
3
Institute of Materials Research and Engineering, A*STAR (Agency for Science, Technology and Research), 2 Fusionopolis Way, Innovis, #08-03, Singapore 138634, Singapore
4
Department of Civil and Environmental Engineering, University of California at Berkeley, Berkeley 94720, CA, USA
*
Author to whom correspondence should be addressed.
Academic Editor: Luciano Feo
Materials 2017, 10(1), 75; https://doi.org/10.3390/ma10010075
Received: 7 November 2016 / Revised: 23 December 2016 / Accepted: 9 January 2017 / Published: 18 January 2017
MgO cements have great potential for carbon sequestration as they have the ability to carbonate and gain strength over time. The hydration of reactive MgO occurs at a similar rate as ordinary Portland cement (PC) and forms brucite (Mg(OH)2, magnesium hydroxide), which reacts with CO2 to form a range of hydrated magnesium carbonates (HMCs). However, the formation of HMCs within the MgO–CO2–H2O system depends on many factors, such as the temperature and CO2 concentration, among others, which play an important role in determining the rate and degree of carbonation, the type and stability of the produced HMCs and the associated strength development. It is critical to understand the stability and transformation pathway of HMCs, which are assessed here through the use of X-ray photoelectron spectroscopy (XPS). The effects of the CO2 concentration (in air or 10% CO2), exposure to high temperatures (up to 300 °C) and curing period (one or seven days) are reported. Observed changes in the binding energy (BE) indicate the formation of different components and the transformation of the hydrated carbonates from one form to another, which will influence the final performance of the carbonated blends. View Full-Text
Keywords: MgO; carbonation; hydration; XPS MgO; carbonation; hydration; XPS
Show Figures

Figure 1

MDPI and ACS Style

Rheinheimer, V.; Unluer, C.; Liu, J.; Ruan, S.; Pan, J.; Monteiro, P.J.M. XPS Study on the Stability and Transformation of Hydrate and Carbonate Phases within MgO Systems. Materials 2017, 10, 75.

Show more citation formats Show less citations formats
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Back to TopTop