Ceramic Expansion by Water Layers on Magnesium Oxide: AB InitioStudy

Aqeel M. Ali¹ and Ali H. Al-Mowali^2,

¹Department of Physics, College of Science, University of Basrah, Basrah, Iraq

²Department of Chmistry, College of Science, University of Basrah, Basrah, Iraq

Cite this paper:
Aqeel M. Ali and Ali H. Al-Mowali. Ceramic Expansion by Water Layers on Magnesium Oxide: AB InitioStudy. American Journal of Materials Science and Engineering. 2013; 1(3):50-53. doi: 10.12691/ajmse-1-3-4

Abstract

MgO hydration is an expansive process. It is used in cement to compensate for shrinkage, but it can be harmful at higher concentrations. First-principles calculations have been used to investigate the electronic properties of the steps of the hydration of MgO using the general gradient approximation GGA functional method within density functional method (DFT). The energy bands along high symmetry directions, energy of hydration and energy of dissociation cut through various planes are presented. The first principles band structure calculations reported here were carried out using Perdew, Burke and Ernzerhof (PBE) method. The calculations have been applied to investigate water adsorption on the (001, 110, 111 and 210) surfaces of MgO crystal. The hydrated MgO surfaces show a similar band structure that of brucite material. Both molecular adsorption and dissociative adsorption have been found to occur. The MgO surfaces have different tendency to interact with water molecules, and they differ in susceptibility disintegration of expansion. The results show that the safest surface is (001) group, while the harmful surfaces are (210) and (111) groups.

Keywords:
ceramic DFT MgO hydration brucite band structure

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References:

[1]	Amaral, L.F., Olivira, I.R., Bonadia, P., Salomao, R. and Pandolfelli, V.C., "Chelants to inhibit magnesia (MgO) hydration" Ceramic international, 37 (5). 1537-1542. Jul.2011.
[2]	Zhang, W., Liu, Z. and Mao, P., "Different additives to inhibit magnesia (MgO) hydration" Advance and materials research, 557-559. 3-7. 2012.
[3]	Zhu, J., Ye, N., Liu, J. and Yang, J., "Evaluation on hydration reactivity of reactive magnesium oxide prepared by calcining magnesite at lower temperatures" Industrial and engineering chemistry research, 52 (19). 6430-6437. 2013.
[4]	Vandeperre, L., Liska, M. and Al-tabbaa, A., "Hydration and mechanical properties of magnesia, pulverized fuel ash, and Portland cement blends" Journal of materials in civil engineering, 20 (5). 375-383. May 2008.
[5]	Karalti, O., Dario Alfe, D., Michael J. Gillan, M.J. and Jordan, K.J., " Adsorption of a water molecule on the MgO(100) surface as described by cluster and slab models" Phys. Chem. Chem. Phys., 14. 7846-7853. 2012.
[6]	Abdel Halim, W.S. and Shalabi, A.S., "Surface morphology and interaction between water and MgO, CaO and SrO surfaces Periodic HF and DFT calculations" Applied Surface Science, 221. 53-61. 2004.
[7]	Sung Hwan Moon, S.H., Heo, T.W., Park, S.Y., Kim, J.H. and Kim, H.J., "The Effect of the Dehydration of MgO Films on their XPS Spectra and Electrical Properties" Journal of The Electrochemical Society, 154 (12). J408-J412. 2007.
[8]	Heidberg, B., Bredow, T., Littmann, K. and Jug, K., "Ceramic hydration with expansion. The structure and reaction of water layers on magnesium oxide. A cyclic cluster study" Materials Science-Poland, 23( 2). 501-508. 2005.
[9]	Scamehorn, C.A., Hess, A.C. and McCarthy, M.I., "Observation of the second ordered phase of water on the MgO(100) surface: Low energy electron diffraction and helium atom scattering studies" J. Chem. Phys., 99 (4). 2786.1993.
[10]	Du, G., Xue, Q., Ding, H. and Li, Z., "Mechanochemical effect of brucite powder in a wet ultrafine grinding process" Indian journal of engineering and material science, 20. 7-13. Feb.2013.
[11]	Moon, K., Lee, S., and Han, H., "Nearly Flat Donor and Acceptor Bands of Two-Dimensional Photonic Crystals with Periodic Vacancy Defects" Journal of the Korean Physical Society, 50 (2). 532-536. Feb. 2007.
[12]	Scamehorn, C.A., Harrison, N.M., McCarthy, M.I.," Water chemistry on surface defect sites: Chemidissociation versus physisorption on MgO(001)" J. Chem. Phys., 101 (2). 1547-1554. Jul.1994.
[13]	Li, F., Chen, Y. and Long, S., "Influnce of MgO expansive agent on behavior of cement pastes and concrete" The Arabian Journal for Science and Engineering, 35( 1B). Apr.2010.
[14]	Langel, W. and Parrinello, M., "Ab initio molecular dynamics of H2O adsorbed on solid MgO" J. Chem. Phys., 103. 3240. 1995.
[15]	McCarthy, M.I., Schenter, G.K., Scamehorn, C.A. and Nicholas, J.B., " Structure and dynamics of the water/MgO interface''" J. Phys. Chem., 100. 16989-16995. 1996.
[16]	Ciesla, F. and Lauretta, D., "Radial migration and dehydration of phyllosilicates in the solar nebula" Earth Planet. Sci Let., 231. 1-8. 2005.
[17]	Amsterdam density functional modeling suite, scientific computing and modeling, ADF 2012.01, 2012.
[18]	Perdew J. P., Burke K. and Ernzerhof M. (1996) Phys. Rev. Lett., 77, 3865.