Introducing Ag in Ba_(0.9)La_(0.1)FeO_(3-δ):Combining cationic substitution with metal particle decoration  

作　　者：Alessio Belotti Jiapeng Liu Antonino Curcio Jian Wang Zheng Wang Emanuele Quattrocchi Mohammed BEffat Francesco Ciucci 

机构地区：[1]Department of Mechanical and Aerospace Engineering,The Hong Kong University of Science and Technology,Hong Kong,China [2]Department of Chemistry,College of Science,Seoul National University,Seoul,South Korea [3]Department of Chemical and Biological Engineering,The Hong Kong University of Science and Technology,Hong Kong,China

出　　处：《Materials Reports(Energy)》2021年第2期77-89,共13页材料导报（能源）（英文）

基　　金：The authors gratefully acknowledge the Research Grant Council of Hong Kong for support through the projects 16201820,and 16206019.

摘　　要：BaFeO_(3-δ)-derived perovskites are promising cathodes for intermediate temperature solid oxide fuel cells.The activity of these perovskites depends on the number of oxygen vacancies in their lattice,which can be tuned by cationic substitution.Our first-principle calculations show that Ag is a promising substitute for the Fe site,resulting in a reduced oxygen vacancy formation energy compared with the pristine BaFeO_(3-δ).Ag has limited solubility in perovskites,and its introduction generates an Ag metal secondary phase,which influences the cathode performances.In this work,we investigate the matter,using a Ba0:9La0:1Fe_(1-x)AgxO_(3-δ)series of materials as a case study.Acknowledging the limited solubility of Ag in Ba0:9La0:1Fe_(1-x)AgxO_(3-δ),we aim to distinguish the effects of Ag substitution from those of the Ag secondary phase.We observed that Ag substitution increases the number of oxygen vacancies,confirming our calculations,and facilitates the oxygen incorporation.However,Ag substitution lowers the number of holes,in this way reducing the electronic p-type conductivity.On the other hand,Ag metal positively affects the electronic conductivity and helps the redistribution of the electronic charge at the cathode-electrolyte interface.

关 键 词：Solid oxide fuel cells Mixed ionic electronic conductors Ag substitution Ag particles decoration BaFeO_(3-δ)-derived perovskites 

分 类 号：O64[理学—物理化学]