The proton uptake process in double perovskite triple ionic-electronic conducting oxides for protonic ceramic cells. Issue 30 (18th July 2022)

• Record Type: Journal Article
• Authors: Im, Seunghyeok; Berk, Muhammet Ali; Yang, Sungeun; Kim, Byung-Kook; Yoon, Kyung Joong; Son, Ji-Won; Lee, Jong-Ho; Ji, Ho-Il
• Is Part Of: Journal of materials chemistry. Volume 10:Issue 30(2022)
• Page Start: 16127
• Page End: 16136
• Publication Date: 2022-07-18
• Subjects: Materials -- Research -- Periodicals; Chemistry, Analytic -- Periodicals; Environmental sciences -- Research -- Periodicals; 543.0284
• DOI: 10.1039/d2ta03522g
• Languages: English
• ISSNs: 2050-7488

Abstract

Abstract : The proton uptake mechanism in a triple conducting oxide, PrBa0.5 Sr0.5 Co1.5 Fe0.5 O5+ δ, is comprehensively investigated based on defect chemistry and experimental analyses of mass and conductivity changes under dry and humidified atmospheres. Abstract : Triple ionic-electronic conducting oxides, in which electron holes, oxygen ions, and protons are simultaneously mobile, are garnering massive attention as potential oxygen electrodes in protonic ceramic cells. While their high electrocatalytic activity and proton transport ability generally provide opportunities for enhanced performance of electrochemical cells, the lack of fundamental knowledge on the proton uptake mechanism hinders the rational modification and design of materials. Herein, we investigate the proton uptake mechanism in double-perovskite PrBa0.5 Sr0.5 Co1.5 Fe0.5 O5+ δ (PBSCF), a widely used triple ionic-electronic conducting oxide. The proton solubility of PBSCF is examined by direct observation of protons using secondary ion mass spectrometry. We then comprehensively discuss the correlations between previously hypothesized proton uptake mechanisms (hydration vs. hydrogenation) and experimentally measured properties such as mass and conductivity changes. This work provides a guideline for establishing the design principles of triple ionic-electronic conducting oxides based on mechanistic understanding.