(a) Gadolinium doped ceria (GDC), Ce1-xGdxO2-x/2-8 (0.0 ≤x≤0.2) is an important solid electrolyte being developed for intermediate temperature solid oxide fuel cells (IT- SOFCs). (i) Using Kröger-Vink notation, give an equation describing defect formation in GDC. (ii) Bearing in mind your answer to part (i) and the requirements for fast ionic transport in solids, what is the main charge carrier likely to be? Explain your answer. (iii) The value of 8 is negligible at room temperature, but increases at higher temperature. Explain this phenomenon and describe what effect it would likely have on the conductivity of GDC.

(a) Gadolinium doped ceria (GDC), Ce1-xGdxO2-x/2-8 (0.0 ≤x≤0.2) is an important solid electrolyte being developed for intermediate temperature solid oxide fuel cells (IT- SOFCs). (i) Using Kröger-Vink notation, give an equation describing defect formation in GDC. (ii) Bearing in mind your answer to part (i) and the requirements for fast ionic transport in solids, what is the main charge carrier likely to be? Explain your answer. (iii) The value of 8 is negligible at room temperature, but increases at higher temperature. Explain this phenomenon and describe what effect it would likely have on the conductivity of GDC.

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter23: Voltammetry

Section: Chapter Questions

Problem 23.14QAP

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