A first-principles study of the piezoelectric properties of Niobium and Tantalum Pentoxides
Journal Title: TecnoLógicas - Year 2017, Vol 20, Issue 40
Abstract
Nb2O5and Ta2O5are wide-bandgap semiconductor oxides that have attracted great interest in recent years due to their technological applications, such as in electronics, telecommunications or photocatalysis. Because of this, we present a study based on first-principles calculations of the piezoelectric properties of the Z and βphases of Ta2O5as well as the Z and P phases of Nb2O5by using the Density Functional Theory and the Generalized Gradient Approximation with PBEsol parameterization. Once the equilibrium geometry was determined for each of these phases, we made a calculation using the linear response theory to determine the piezoelectric tensor associated with each phase. We discovered that the Z phase of both compounds presents good piezoelectric response. Additionally, β-Ta2O5does not show such response.
Authors and Affiliations
Olga M. Giraldo-Giraldo, Santiago Pérez-Walton, Jorge M. Osorio-Guillén
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