Electrochemical and microstructure study of ceramic composite based on BaCo0.4Fe0.4Zr0.2 O 3 − δ : BaZr0.7Ce0.2Y0.1O 3 − δ as a steam electrode interlayer in proton-conducting electrolysis cells

International Journal of Hydrogen Energy, vol. 177, pp. 151426

Abstract

A primary challenge in advancing proton-conducting electrolysis cells for H 2 generation lies in enhancing the performance and durability of the steam electrode. This paper addresses common delamination issues, frequently observed during cell operation due to thermal expansion mismatch, by introducing a novel functional layer — an intermediate component intended to be placed between the steam electrode and the electrolyte. We systematically investigate the optimal composition of this functional layer, based on BaCo 0.4 Fe 0.4 Zr 0.2 O 3 − δ (BCFZ442)/BaZr 0.7 Ce 0.2 Y 0.1 O 3 − δ (BZCY721), alongside its associated ink rheology. The electrochemical performance of the composite functional layer is comprehensively assessed on symmetrical cells under humidified air within the temperature range of 200 to 700 °C. Furthermore, detailed microstructural analyses are conducted before and after cell operation to provide critical insights for future improvements. The study also explores the impact of layer thickness, influenced by varying ethyl cellulose (EC) binder weight fractions, on the area-specific resistance (ASR). The BCFZ: BZCY (70:30) composite, prepared with 3 wt% EC, demonstrates the lowest area-specific resistance of 0.99 Ω cm 2 and an activation energy of 0.94 eV at 600 °C. These findings suggest that the developed composite maintains optimal charge transfer kinetics and conductivity, simultaneously preventing delamination. • This study proposes an interlayer between the electrolyte and the steam electrode. • This study systematically optimizes the screen-printing paste formulation. • This work highlights binder effects on microstructure and electrochemical output.

Authors 8

1. Yuan Zeng corresponding Aachen Department of Ceramics and Refractory Materials Institute of Mineral Engineering (GHI)

   Forschungszentrum Jülich · RWTH Aachen University

   Affiliation as printed

   Department of Ceramics and Refractory Materials, Institute of Mineral Engineering, RWTH Aachen University, Aachen, 52078, Germany

   Institute of Energy Materials and Devices – Materials Synthesis and Processing (IMD-2), Forschungszentrum Jülich GmbH, Jülich, 52428, Germany

2. Laura–Alena Schaefer Aachen Department of Ceramics and Refractory Materials Institute of Mineral Engineering (GHI)

   Forschungszentrum Jülich · RWTH Aachen University

   Affiliation as printed

   Department of Ceramics and Refractory Materials, Institute of Mineral Engineering, RWTH Aachen University, Aachen, 52078, Germany

   Institute of Energy Materials and Devices – Materials Synthesis and Processing (IMD-2), Forschungszentrum Jülich GmbH, Jülich, 52428, Germany

3. Muhammad Shirjeel Khan

   Forschungszentrum Jülich

   Affiliation as printed

   Institute of Energy Materials and Devices – Materials Synthesis and Processing (IMD-2), Forschungszentrum Jülich GmbH, Jülich, 52428, Germany

4. Kwati Leonard

   Kyushu University

   Affiliation as printed

   Center for Energy System Design, International Institute for Carbon-Neutral Energy Research (I2CNER) Kyushu University, 744 Motooka, Nishi-ku, Fukuoka, 819-0395, Japan

5. Norbert Heribert Menzler Aachen Department of Ceramics and Refractory Materials Institute of Mineral Engineering (GHI)

   Forschungszentrum Jülich · RWTH Aachen University

   Affiliation as printed

   Department of Ceramics and Refractory Materials, Institute of Mineral Engineering, RWTH Aachen University, Aachen, 52078, Germany

   Institute of Energy Materials and Devices – Materials Synthesis and Processing (IMD-2), Forschungszentrum Jülich GmbH, Jülich, 52428, Germany

6. Olivier Guillon Aachen Department of Ceramics and Refractory Materials Institute of Mineral Engineering (GHI)

   Forschungszentrum Jülich · Indian Institute of Technology Madras · RWTH Aachen University

   Affiliation as printed

   Department of Ceramics and Refractory Materials, Institute of Mineral Engineering, RWTH Aachen University, Aachen, 52078, Germany

   Institute of Energy Materials and Devices – Materials Synthesis and Processing (IMD-2), Forschungszentrum Jülich GmbH, Jülich, 52428, Germany

   Research Center on Ceramic Technologies for Futuristic Mobility, Institute of Eminence (IoE), Indian Institute of Technology-Madras (IIT Madras), Chennai, 600036, India

7. Mariya Ivanova corresponding

   Forschungszentrum Jülich

   Affiliation as printed

   Institute of Energy Materials and Devices – Materials Synthesis and Processing (IMD-2), Forschungszentrum Jülich GmbH, Jülich, 52428, Germany

8. Ravi Kumar corresponding

   Indian Institute of Technology Madras

   Affiliation as printed

   Laboratory for High Performance Ceramics, Department of Metallurgical and Materials Engineering, Indian Institute of Technology-Madras (IIT Madras), Chennai, 600036, India

   Research Center on Ceramic Technologies for Futuristic Mobility, Institute of Eminence (IoE), Indian Institute of Technology-Madras (IIT Madras), Chennai, 600036, India