Electrochemical properties of La0.5Sr0.5Fe0.95Mo0.05O3- δ as cathode materials for IT-SOEC

Yunting Hou; Yadun Wang; Lijun Wang; Qifei Zhang; Kuo-Chih Chou

doi:10.1039/d1ra06197f

Electrochemical properties of La_0.5Sr_0.5Fe_0.95Mo_0.05O_{3- δ} as cathode materials for IT-SOEC

RSC Adv. 2021 Sep 28;11(51):32077-32084. doi: 10.1039/d1ra06197f. eCollection 2021 Sep 27.

Authors

Yunting Hou^{1

2}, Yadun Wang¹, Lijun Wang¹, Qifei Zhang¹, Kuo-Chih Chou²

Affiliations

¹ Collaborative Innovation Center of Steel Technology, University of Science and Technology Beijing Beijing 100083 China lijunwang@ustb.edu.cn.
² State Key Laboratory of Advanced Metallurgy, University of Science and Technology Beijing Beijing 100083 China.

Abstract

Solid oxide electrolysis cells (SOECs) are a new type of high-efficiency energy conversion device that can electrolyze CO₂ efficiently and convert electricity into chemical energy. However, the lack of efficient and stable cathodes hinders the practical application of CO₂ electrolysis in SOECs. Herein, a novel perovskite oxide La_0.5Sr_0.5Fe_0.95Mo_0.05O_3-δ (LSFMo) is synthesized and used as a cathode for SOECs. The introduction of Mo significantly improves the CO₂ tolerance of the material in a reducing atmosphere and solves the problem of SrCO₃ generation in the La_0.5Sr_0.5FeO_3-δ material. Mo ion doping promotes the conductivity in a reducing atmosphere and increases the oxygen deficiencies of the material, which lowers the ohmic resistance (R _s) of the material and significantly improves the CO₂ adsorption and dissociation in the middle-frequency of polarization resistance (R _p). For example, R _p decreases from 0.49 to 0.24 Ω cm² at 800 °C under 1.2 V. Further, the reduction of R _s and R _p increases the performance improvement, and the current density is increased from 1.56 to 2.13 A cm^-2 at 800 °C under 2 V. Furthermore, LSFMo shows reasonable short-term stability during the 60 h stability test.