A Synergistic Three-Phase, Triple-Conducting Air Electrode for Reversible Proton-Conducting Solid Oxide Cells

Weilin Zhang; Yucun Zhou; Xueyu Hu; Yong Ding; Jun Gao; Zheyu Luo; Tongtong Li; Nicholas Kane; Xiao-Ying Yu; Tanguy Terlier; Meilin Liu

doi:10.1021/acsenergylett.3c01251

A Synergistic Three-Phase, Triple-Conducting Air Electrode for Reversible Proton-Conducting Solid Oxide Cells

ACS Energy Lett. 2023 Sep 1;8(10):3999-4007. doi: 10.1021/acsenergylett.3c01251. eCollection 2023 Oct 13.

Authors

Weilin Zhang¹, Yucun Zhou¹, Xueyu Hu¹, Yong Ding¹, Jun Gao², Zheyu Luo¹, Tongtong Li^{1

3}, Nicholas Kane¹, Xiao-Ying Yu⁴, Tanguy Terlier⁵, Meilin Liu¹

Affiliations

¹ School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0245, United States.
² Energy and Environment Directorate, Pacific Northwest National Laboratory, Richland, Washington 99354, United States.
³ Energy Materials and Surface Sciences Unit, Okinawa Institute of Science and Technology Graduate University, 1919-1 Tancha, Onna-son, Kunigami-gun, Okinawa 904-0495, Japan.
⁴ Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 99354, United States.
⁵ Shared Equipment Authority, SIMS Laboratory, Rice University, Houston, Texas 77005, United States.

Abstract

Reversible proton-conducting solid oxide cells (R-PSOCs) have the potential to be the most efficient and cost-effective electrochemical device for energy storage and conversion. A breakthrough in air electrode material development is vital to minimizing the energy loss and degradation of R-PSOCs. Here we report a class of triple-conducting air electrode materials by judiciously doping transition- and rare-earth metal ions into a proton-conducting electrolyte material, which demonstrate outstanding activity and durability for R-PSOC applications. The optimized composition Ba_0.9Pr_0.1Hf_0.1Y_0.1Co_0.8O_3-δ (BPHYC) consists of three phases, which have a synergistic effect on enhancing the performance, as revealed from electrochemical analysis and theoretical calculations. When applied to R-PSOCs operated at 600 °C, a peak power density of 1.37 W cm^-2 is demonstrated in the fuel cell mode, and a current density of 2.40 A cm^-2 is achieved at a cell voltage of 1.3 V in the water electrolysis mode under stable operation for hundreds of hours.