Theoretical study of electronic properties and chemical stability of cubic phase zirconia nanowires

Abstract

Abstract Zirconia bulk is one of the most studied materials around the world due to different properties such as a high melting temperature, biocompatibility and high thermal expansion, among many others. However, there is little experimental research about Zirconia nanowires and until now there are few theoretical papers on the subject. In this work, Density Functional Theory (DFT) calculations on bare ZrO2 nanowires with diameter variation were performed. In order to get the more accurate parameters for calculation on nanowires, we employed the Murnaghan equation of state in a perfect cubic crystal of ZrO2 (c-ZrO2) and we compared the results obtained with some experimental data as well as the lattice parameter and the bulk modulus. The nanowires were grown along the [1 1 1] direction with five different diameters. All calculations were carried out by DFT implemented in SIESTA code. According to our results, the functional PBE of the Generalized Gradient Approximation (GGA-PBE) is the more accurate functional for describing the E xc on ZrO2. The calculation of formation and surface energies shows that these nanowires are chemically stable. Furthermore, nanowires larger than 8.78 Å present a direct band gap. These results indicate the possibility of applying ZrO2 nanowires in the optoelectronic field.