Hidden symmetry lowering, nanoscale order-disorder transition and ionic conductivity in Na1/2-xLa1/2-xBa2xZrO3

被引：0

作者：

Brennan, Mia J. ^{[1
]}

Marlton, Frederick P. ^{[2
]}

Mohanty, Biswaranjan ^{[3
]}

Dupre, Nicolas ^{[4
]}

Johannessen, Bernt ^{[5
,6
]}

Avdeev, Maxim ^{[1
,7
]}

Cuello, Gabriel J. ^{[8
]}

Wagstaff, Oliver J. ^{[9
]}

Yang, Frederick Z. T. ^{[10
]}

Schmid, Siegbert ^{[1
]}

Ling, Chris D. ^{[1
]}

机构：

[1] Univ Sydney, Sch Chem, Sydney, NSW 2006, Australia

[2] Univ Technol Sydney, Fac Sci, Ctr Clean Energy Technol, Sch Math & Phys Sci, Sydney, NSW 2007, Australia

[3] Univ Sydney, Sydney Analyt Core Res Facil, Sydney, NSW 2006, Australia

[4] Nantes Univ, Inst Materiaux Nantes Jean Rouxel, CNRS, IMN, F-44000 Nantes, France

[5] Australian Nucl Sci & Technol Org, Australian Synchrotron, 800 Blackburn Rd, Clayton, Vic 3168, Australia

[6] Univ Wollongong, Inst Superconducting & Elect Mat ISEM, Fac Engn & Informat Sci EIS, Wollongong, NSW 2500, Australia

[7] Australian Nucl Sci & Technol Org, Australian Ctr Neutron Scattering, New Illawarra Rd, Lucas Heights, NSW 2234, Australia

[8] Inst Laue Langevin, 71 Ave Martyrs, F-38042 Grenoble 9, France

[9] Univ Durham, Dept Chem, Stockton Rd, Durham DH1 3LE, England

[10] Univ Oxford, Dept Chem, Chem Res Lab, 12 Mansfield Rd, Oxford, England

来源：

JOURNAL OF MATERIALS CHEMISTRY A | 2025年 / 13卷 / 07期

基金：

澳大利亚研究理事会;

关键词：

X-RAY; POWDER DIFFRACTION; PEROVSKITES; CRYSTAL; NMR; ELECTROLYTE;

D O I：

10.1039/d4ta07291j

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

This work concerns the local/nano-scale effects of Ba2+ substitution on the structure and ionic conductivity of Na1/2-xLa1/2-xBa2xZrO3, 2/32 <= x <= 8/32. Samples were investigated in detail by neutron total scattering analysis in combination with synchrotron X-ray and neutron powder crystallography, X-ray absorption spectroscopy, and solid-state nuclear magnetic resonance spectroscopy. Substitution of Ba2+ onto the perovskite A-site causes all members of the series to adopt a crystallographic average I4/mcm symmetry analogous to the high temperature phase of Na1/3La1/3Sr1/3ZrO3, but a deviation from Vegard's law at x = 6/32 indicates the presence of more complex nanoscale structural features. Above this deviation, analysis of neutron total scattering and extended X-ray absorption fine structure data show that the structure can only be modelled accurately by lowering the symmetry from tetragonal I4/mcm to orthorhombic P42/nmc space group to capture the local features. Further refinements conducted using reverse Monte Carlo methods allowed for the quantification of cation ordering, octahedral tilting angles, and element-specific thermal motion. Based on this model, we used a combination of bond valence sum energy mapping and molecular dynamics simulations to develop a detailed model of the effects of Ba2+ substitution on Na+ conductivity in Na1/2-xLa1/2-xBa2xZrO3.

引用

页码：4960 / 4970

页数：11

共 50 条

[1] 23Na multiple-quantum MAS NMR of the perovskites NaNbO3 and NaTaO3 [J].