Effect of Oxygen Defects Blocking Barriers on Gadolinium Doped Ceria (GDC) Electro-Chemo-Mechanical Properties

Abstract

Some oxygen defective metal oxides, such as cerium and bismuth oxides, have recently shown exceptional electrostrictive properties that are even superior to the best performing lead-based electrostrictors, e.g. lead-magnesium-niobates (PMN). Compared to piezoelectric ceramics, electromechanical mechanisms of such materials do not depend on crystalline symmetry, but on the concentration of oxygen vacancy in the lattice. In this work, we investigate for the first time the role of oxygen defect configuration on the electro-chemo-mechanical properties. This is achieved by tuning the oxygen defects blocking barrier density in polycrystalline gadolinium doped ceria with known oxygen vacancy concentration, Ce0.9Gd0.1O2-x,x= 0.05. Nanometric starting powders of ca. 12 nm are sintered in different conditions, including field assisted spark plasma sintering (SPS), fast firing and conventional method at high temperatures. These approaches allow controlling grain size and Gd-dopant diffusion, i.e. via thermally driven solute drag mechanism. By correlating the electro-chemo-mechanical properties, we show that oxygen vacancy distribution in the materials play a key role in ceria electrostriction, overcoming the expected contributions from grain size and dopant concentration.

Cited by in corpus (4)

• Atomic-scale insights into electro-steric substitutional chemistry of cerium oxide
• The Role of Oxygen Defects on the Electro-Chemo-Mechanical Properties of Highly Defective Gadolinium Doped Ceria
• Enhanced Electromechanical Response in Defective Sm and Nd Co-doped Ceria
• Effect of Cold Sintering Process (CSP) on the Electro-Chemo-Mechanical Properties of Gd-doped Ceria (GDC)