Articles - Indirect monitoring of mixed conduction in La2NiO4+δ-based systems using impedance spectroscopy
- Yong Hoon Kima, Seung Muk Baea, Chan-Rok Parka, Sang-Yun Jeonb, Moon-Bong Choib, Sun-Ju Songb, Young-Sung Yooc and Jin-Ha Hwanga,*
- a Department of Materials Science and Engineering, Hongik University, 72-1 Sangsu-dong, Mapo-gu, Seoul 121-791, Korea b Department of Materials Science and Engineering, Chonnam National University, 300 Yongbong-ro, Buk-gu, Gwangju 500- 757, Korea c Green Growth Technology Laboratory, Korea Electric Power Research Institute, 65 Munji-Ro, Yuseong-Gu, Daejeon 305-760, Korea
Abstract
The Electrochemical activities of updoped (La2NiO4+δ) and Ba-doped lanthanum nicklate (La1,85Ba0.15NiO4+δ) materials were estimated using impedance spectroscopy and digital image processing. Mixed conduction was evaluated with an ionicconducting, Gd2O3-doped CeO2 probe. Geometric constriction between the ionic probe and mixed-conducting materials allowed for the relative contribution of ionic conduction with regard to electronic conductivity in terms of polarization losses originating from the interface between the oxygen conductor and the mixed-conduction materials. The electrochemical loss in doped La1,85Ba0.15NiO4+δ was significantly lower than that measured in updoped La2NiO4+δ. Therefore, Ba-doped lanthanum nicklate appears to provide better ionic conduction compared to the updoped material.
Keywords: Mixed conduction, Impedance spectroscopy, Electrochemical losses, La2NiO4
This Article
Copyright 2019 International Orgranization for Ceramic Processing. All rights reserved.Clean-Energy Research Institute(CRI), Hanyang University, 222, Wangsimni-ro, Seongdong-gu, Seoul, 04763, Korea
E-mail: jcpr@hanyang.ac.kr