Relative Occurrence of Oxygen-Vacancy Pairs in Yttrium-Containing Environments of Y2O3-Doped ZrO2 Can Be Crucial to Ionic Conductivity

2017 ◽  
Vol 121 (27) ◽  
pp. 14534-14543 ◽  
Author(s):  
Methary Jaipal ◽  
Abhijit Chatterjee
1988 ◽  
Vol 135 ◽  
Author(s):  
P.K. Moon ◽  
H.L. Tuller

AbstractThe pyrochlore solid solution Gd2(Zrx Til−x)2O7, was found to be an attractive system for investigating the relationship between composition, structural disorder and ionic conductivity. Both cation and anion order parameters were found to decrease systematically with increasing substitution of Zr for Ti leading ultimately to intrinsic fast oxygen ion conductivity in the solid solution. The degree of intrinsic disorder was determined quantitatively from doping experiments and was found to be equal to l.0×lO39 exp(-O.24±0.03eV/kT)cm−6sfor x = 0.3 and substantially larger for higher values of x. Oxygen vacancy mobilities, on the other hand, were found to be relatively independent of x with values of μv, = 0.15exp(-0.78 ± 0.02 eV/kT)cm2V−1s−1. These, and more recent results, on Y2 (ZrxTil−x)2O7, are discussed in the context of the similarities between the pyrochlore and fluorite phases.


1995 ◽  
Vol 393 ◽  
Author(s):  
Anbin Yu ◽  
Sossina M. Haile

ABSTRACTA serious concern with present designs of solid oxide fuel cells is the requirement that “triple-point junctions” exist, sites at which the cathode, electrolyte and oxidizing gas are in simultaneous contact. Only at these junctions can the cathode catalyze the reduction of oxygen into 0= ions and initiate their subsequent transport through the electrolyte. Enhanced ionic conductivity in the cathode material may increase the surface area over which reduction can take place and relax the triple-point constraint. To this end, we have examined the electrical and structural properties of LaCo1-xMgx03-δ materials under various atmospheres. Oxygen ion transport in this and related ABO3 perovskites takes place via oxygen vacancy migration. We have opted to investigate the effect of Mg doping on the transition metal site in an effort to maintain a significant oxygen vacancy concentration in oxidizing atmospheres (as would be encountered during fuel cell operation) and to isolate the effects of A- and B-site doping.


RSC Advances ◽  
2017 ◽  
Vol 7 (26) ◽  
pp. 16163-16172 ◽  
Author(s):  
C. A. López ◽  
J. C. Pedregosa ◽  
M. T. Fernández-Díaz ◽  
J. A. Alonso

A substantially higher ionic motion can be achieved by partially replacing Mo(vi) by Ti(iv) cations in the novel Sr11Mo4−xTixO23−δ (with x = 0.0, 0.5 and 1.0) electrolyte oxides, successfully enhancing the oxygen vacancy level.


1994 ◽  
Vol 369 ◽  
Author(s):  
Tae-Hwan Yu ◽  
Harry L. Tuller

AbstractElectrical conductivity measurements were performed on Gd2Sn207 as a function of temperature, P02 and Ca doping concentration. An effective frenkel constant and oxygen vacancy mobility were derived. The high level of intrinsic anion disorder found in this study is consistent with expectations based on the cation radius ratio (rA/rB) which was earlier found to be important in determining anion disorder in A2B207 pyrochlore compounds [1]. The magnitude of the ionic conductivity in Gd2Sn2O7 was found to be depressed relative to Gd2(Til-xZrx)207 based systems due to a high oxygen vacancy migration energy.


2019 ◽  
Vol 68 (22) ◽  
pp. 227701
Author(s):  
Hui Tang ◽  
Xin-Gui Tang ◽  
Yan-Ping Jiang ◽  
Qiu-Xiang Liu ◽  
Wen-Hua Li

2018 ◽  
Vol 122 (11) ◽  
pp. 5871-5880 ◽  
Author(s):  
Xiaoping Han ◽  
Noureddine Amrane ◽  
Zongsheng Zhang ◽  
Maamar Benkraouda

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