As fossil energy sources gradually deplete, the global demand for energy transformation is becoming increasingly urgent. Proton Ceramic Electrolyte Cells (PCECs), as a novel energy conversion device, are demonstrating significant potential in the field of clean energy. Compared to traditional Solid Oxide Electrolysis Cells, PCECs have gained widespread attention in recent years due to their low operating temperature and advantages in gas separation. In PCECs, when water vapor is introduced into the steam electrode and a certain voltage is applied, the fuel electrode is capable of producing high-purity hydrogen gas. Despite the widespread attention on PCECs, the stability of the steam electrode under high-humidity conditions remains a major obstacle to their large-scale commercial application. Over the past decade, many studies have focused on improving the stability of PCECs. Although certain progress has been made through modification methods such as doping, these advancements still do not meet the requirements for commercial applications.
Recently, a team of material scientists led by Lin Ge from Nanjing Tech University, China, reported the first composite steam electrode for Protonic Ceramic Electrolysis Cells (PCECs). This electrode consists of a double perovskite PrBaMn2O5+δ (PBM) and a durable proton conductor BaZr0.85Y0.15O3-δ (BZY), with in situ deposition of nano PrOx catalysis. Phase structure (XRD, SEM, TEM) and electrochemical performance (EIS, thermal expansion coefficients, total conductivity and electrolysis current) analyses have demonstrated that the composite steam electrode exhibits excellent stability and superior electrical performance. This work not only highlights the advantages of the composite steam electrodes but also confirms the superior proton conduction of the cube-shaped BZY/PBM interface compared to nanosized BZY.
The team published their work in Journal of Advanced Ceramics on January 14, 2025.
"In this article, we report a novel composite steam electrode for Protonic Ceramic Electrolysis Cells (PCECs) that demonstrates exceptional durability and superior electrical performance. The composite steam electrode is composed of double perovskite PBM, cube-shaped proton conductor BZY, and in situ deposited nano PrOx catalysis. The electrode exhibits remarkable durability under high water vapor concentrations and constant current density. Our findings present a promising strategy for designing durable steam electrodes for PCECs through a rational compositional approach." said Lin Ge, professor at College of Materials Science and Engineering at Nanjing Tech University (China), a senior expert whose research interests focus on the field of proton ceramic electrochemical cells.
"Notably, the facet-boosted interface engineering significantly enhances efficient proton transfer within the composite steam electrode. The electrode composed of cube-shaped BZY microcrystals and PBM demonstrates significantly higher proton conductivity, with an entire order of magnitude improvement compared to electrodes made with nanosized BZY. Our investigation about cube-shaped BZY and nanosized BZY exemplifies efficient MIEC/proton conductor interface design." said Lin Ge.
Cube-shaped BZY exhibits higher proton conductivity and larger grain size (>1μm) than nanosized BZY. "In our previous research, we found that cube-shaped BZY exhibited superior conductivity and enhanced durability against Ba evaporation and Y segregation. Additionally, the cube-shaped BZY/PBM interface may offer an extra pathway for proton conduction in composite steam electrodes. Our findings complement and extend the 'job-sharing' mechanism in the field of electrochemistry, providing valuable insights into the design of efficient composite electrodes." said Lin Ge.
PBM-BZY-PrOx composite steam electrode exhibits reliable total conductivity and excellent stability in high humidity. The thermal expansion coefficient (TEC) of PBM-BZY-PrOx composite steam electrode is 11.51×10−6 K−1, which is much closer to that of the electrolyte. "The TEC is expected to improve electrode-electrolyte interfacial contact and enhance long-term operational durability." said Lin Ge.
Other contributors include Xiaole Yu, Bangze Wu, Zhexiang Yu, Bingyu He, Zhanheng Jin, Zenan Zhao, Han Chen, Yifeng Zheng and Sheng Cui from the college of Materials Science and Engineering at Nanjing Tech University in Jiangsu, China.
This work was supported by National Natural Science Foundation of China (No. 51502136 and No. 21978133), the Natural Science Foundation of Jiangsu Province (BK 20211260), the Priority Academic Program Development (PAPD) of Jiangsu Higher Education Institutions and Top-notch Academic Programs Project of Jiangsu Higher Education Institutions (TAPP).
About Author
Lin Ge is associate Professor and Master's Supervisor at Nanjing Tech University, Deputy Director of the Department of Inorganic Materials. His main research focuses on clean energy conversion materials, fast ion-conducting ceramics, porous ceramics, inorganic binders, and other areas. In recent years, he has led several projects as the principal investigator, including national key R&D projects, National Natural Science Foundation of China, Jiangsu Provincial Natural Science Foundation, China Postdoctoral Fund, Jiangsu Postdoctoral Funding Projects, and various industry-sponsored projects. He has published more than 60 SCI papers in journals such as Adv. Funct. Mater., Appl. Catal. B-Environ., J. Mater. Chem. A, Energ. Convers. Manage., J. Eur. Ceram. Soc., J. Power Sources, Electrochim. Acta, Ceram. Int., and others, and holds multiple authorized invention patents. He has been a long-time reviewer for journals including J. Energy Chem., Green Energy Environ., J. Power Sources, J. Am. Ceram. Soc., Ceram. Int., Energy, Fuel, J. Alloys Compd., and Sep. Purif. Technol.. He serves as a council member of the Special Ceramics Branch of the Chinese Ceramic Society, an assistant editorial board member for the Journal of Advanced Ceramics, and an editorial board member for Advanced Ceramics.
About Journal of Advanced Ceramics
Journal of Advanced Ceramics (JAC) is an international academic journal that presents the state-of-the-art results of theoretical and experimental studies on the processing, structure, and properties of advanced ceramics and ceramic-based composites. JAC is Fully Open Access, monthly published by Tsinghua University Press, and exclusively available via SciOpen . JAC's 2023 IF is 18.6, ranking in Top 1 (1/31, Q1) among all journals in "Materials Science, Ceramics" category, and its 2023 CiteScore is 21.0 (top 5%) in Scopus database. ResearchGate homepage: https://www.researchgate.net/journal/Journal-of-Advanced-Ceramics-2227-8508
About SciOpen
SciOpen is an open access resource of scientific and technical content published by Tsinghua University Press and its publishing partners. SciOpen provides end-to-end services across manuscript submission, peer review, content hosting, analytics, identity management, and expert advice to ensure each journal's development. By digitalizing the publishing process, SciOpen widens the reach, deepens the impact, and accelerates the exchange of ideas.