Electronic Structure of Erbium Silicates Investigated by First-Principles Method

Abstract:

Rare earth silicates (RE2_SiO₅ or RE₂Si₂O₇; RE=Er, Lu, Y, Yb etc.) possess a low silica activity and good thermal stability, making them good candidates for EBC top coating materials. We have performed first-principles total energy calculations for the Er₂O₃-SiO₂ pseudo binary system. The crystal lattice parameters and internal atomic coordinates of Er₂SiO₅ and Er₂Si₂O₇ are optimized, and the electronic structure and formation enthalpies are calculated. The present study provides a theoretical basis for exploring practical applications of the materials.

• Periodical: Advanced Materials Research (Volume 650)
• Pages: 167-171
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.650.167
• Online since: January 2013
• Authors: Yi Bo Liu, Li Gen Wang, Chuan Zhang, Li Min Wang, Lei Wang
• Keywords: Density of States, Electronic Structure, Erbium Silicates, First-Principle Calculations

References

[1] K.N. Lee, Key durability issues with mullite-based environmental barrier coatings for Si-based ceramics, Transactions of the ASME, 122 (2000): 632-636.

DOI: 10.1115/1.1287584

[2] R.C. Robinson, J.L. Smialek, SiC recession caused by SiO2 scale volatility under combustion conditions: I, Experimental results and empirical model, J. Am. Ceram. Soc., 82(7) (1999): 1817-1825.

DOI: 10.1111/j.1151-2916.1999.tb02004.x

[3] K.N. Lee, D.S. Fox, N.P. Bansal, Rare-Earth Silicate Environmental Barrier Coatings for SiC/SiC Composites and Si3N4 Ceramics, J. Euro. Ceram. Soc. 25 (2005): 1705-1715.

DOI: 10.1016/j.jeurceramsoc.2004.12.013

[4] G. Kresse, J. Furthmüller, Efficiency of ab-initio total energy calculations for metals and semiconductors using a plane-wave basis set, Comput. Mater. Sci. 6 (1996) 15-50.

DOI: 10.1016/0927-0256(96)00008-0

[5] J. P. Perdew, K. Burke, M. Ernzerhof, Generalized gradient approximation made simple, Phys. Rev. Lett. 77 (1996) 3865-3868.

DOI: 10.1103/physrevlett.77.3865

[6] G. Kresse, J. Joubert, From ultrasoft pseudopotentials to the projector augmented-wave method, Phys. Rev. B 59 (1999) 1758-1775.

DOI: 10.1103/physrevb.59.1758

[7] B. Wang, R.M. Guo, X.J. Wang, L. Wang, Z. Zhou, Composition dependence of the Yb-participated strong up-conversions in polycrystalline ErYb silicate, Opt. Mater. 34 (2012) 1289–1293.

DOI: 10.1016/j.optmat.2012.02.001

[8] W. Y. Ching, Lizhi Ouyang, Yong-Nian Xu, Electronic and optical properties of Y2SiO5 and Y2Si2O7 with comparisons to a-SiO2 and Y2O3, Phys. Rev. B 67 (2003) 245108.

[9] N.A. Toropov, F. Ya. Galakhov, S.F. konovalova, Silicates of the rare earth elements communication 5. phase diagram of the Dy2O3-SiO2 and Er2O3-SiO2 systems, Inorg. Anal. Chem., 8 (1961) 365-1371.

DOI: 10.1007/bf00910094

[10] C. Zhang, F. Zhang, S. L. Chen, and L. G. Wang: to be published.