Electronic properties of A2Zr2O7 (A= Gd, Nd) ceramic

TL;DR

This study investigates the electronic structure and properties of gadolinium and neodymium zirconate ceramics using density functional theory, X-ray spectroscopy, and structural analysis, revealing their electronic and structural characteristics.

Contribution

The paper combines experimental and theoretical methods to analyze the electronic structure and local environment of A2Zr2O7 ceramics, providing new insights into their properties.

Findings

Band gap estimated from UV-Vis spectroscopy.

Face centered cubic crystal structure identified.

Structural and electronic environment characterized by X-ray techniques.

Abstract

The density functional theory with generalized gradient approximation has been used to investigate the electronic structure of gadolinium pyrochlore A2Zr2O7 (A=Gd, Nd) ceramic synthesized in polycrystalline form by solid state reaction. Structural characterization of the compound was done through X-ray diffraction (XRD) followed by Rietveld analysis of the XRD pattern. The Zr-K edge X-ray absorption (XAFS) spectra of A2Zr2O7 (A=Gd, Nd) were analysed together with those Zr-foil, which was used as reference compounds. X-ray photoemission spectroscopy (XPS), X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) for A2Zr2O7 (A=Gd, Nd) has been employed to obtain quantitative structural information on the Zr-local environment. The band gap is estimated using UV-Vis spectroscopy. The crystal structure is face centered cubic, space group being Fd-3m (No. 227). The total energies in this work were calculated using the generalized gradient approximation to DFT plus on-site repulsion (U) method.