TY  - JOUR
AU  - HUANG, Yue
AU  - MO, Yingyu
AU  - LIAN, Wenchao
AU  - QIU, Ruiming
AU  - LIU, Jianping
AU  - LEI, Libin
PY  - 2022
TI  - Theoretical Study on the Ionic Transport Numbers of the Mixed Oxygen Ionic-electronic Conducting Oxides Measured with EMF Method
JO  - Journal of Ceramics
SN  - 2095-784X
SP  - 926
EP  - 933
VL  - 43
IS  - 5
AB  - The mixed oxygen ionic-electronic conducting oxides have been widely used in the fields of solid oxide fuel cells (SOFCs) and solid oxide electrolysis cells (SOECs). The accurate measurement of ionic transport numbers in the mixed oxygen ionic-electronic conducting oxides is significant for their performance optimization and application. Electromotive force (EMF) method is one of the most widely used approaches to measure the ionic transport numbers. However, the measured result of EMF method is the apparent ionic transport number (tiapp). CeO2-based electrolyte was selected as an object, while a model of defect distribution was established. With this model, the distribution of ionic transport numbers across the CeO2-based electrolyte membrane was analyzed and the effect of test conditions on tiapp was examined by using the EMF method, thus evaluating the accuracy of the EMF method. It is demonstrated that the ionic transport number is inhomogeneous across the electrolyte membrane. tiapp is significantly dependent on thickness of the electrolyte membrane when the electrolyte membrane is relatively thin. When there is a large gradient of oxygen chemical potential on both sides of the electrolyte membrane (PO2high/PO2low>1025), tiapp tends to be ionic transport number of the electrolyte layer at high PO2 side and decreases with increasing temperature and the electronic conductivity coefficient of the electrolyte. tiapp tends to be ionic transport number of the electrolyte layer at the low PO2 side when the two sides of the electrolyte layer are in reducing atmospheres(PO2<10‒20 atm). tiapp mainly reflects the ionic transport number of the electrolyte layer at the high PO2 side, when PO2 on the two sides of the electrolyte layer are large (PO2>10‒15 atm).
UR  - https://doi.org/10.13957/j.cnki.tcxb.2022.05.018
DO  - 10.13957/j.cnki.tcxb.2022.05.018