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Lowering the operating temperature of protonic ceramic electrochemical cells to <450 °C


Protonic ceramic electrochemical cells (PCECs) can be employed for power generation and sustainable hydrogen production. Lowering the PCEC operating temperature can facilitate its scale-up and commercialization. However, achieving high energy efficiency and long-term durability at low operating temperatures is a long-standing challenge. Here, we report a simple and scalable approach for fabricating ultrathin, chemically homogeneous, and robust proton-conducting electrolytes and demonstrate an in situ formed composite positive electrode, Ba0.62Sr0.38CoO3δ–Pr1.44Ba0.11Sr0.45Co1.32Fe0.68O6δ, which significantly reduces ohmic resistance, positive electrode–electrolyte contact resistance and electrode polarization resistance. The PCECs attain high power densities in fuel-cell mode (~0.75 W cm−2 at 450 °C and ~0.10 W cm−2 at 275 °C) and exceptional current densities in steam electrolysis mode (−1.28 A cm−2 at 1.4 V and 450 °C). At 600 °C, the PCECs achieve a power density of ~2 W cm−2. Additionally, we demonstrate the direct utilization of methane and ammonia for power generation at <450 °C. Our PCECs are also stable for power generation and hydrogen production at 400 °C.

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Fig. 1: Lowering the operating temperature of PCECs to <450 °C.
Fig. 2: Readily fabricated ultrathin proton-conducting electrolyte using ultrasonic spray coating and negative electrode with low Ba deficiency.
Fig. 3: Crystalline structure, morphology, microstructure and chemical composition of in situ formed BSC + PBSCF positive electrode.
Fig. 4: In situ formed BSC + PBSCF positive electrode reduces ASRP.
Fig. 5: DFT calculations to study the bulk oxygen vacancy formation and oxygen diffusion of PBSCF-1, PBSCF-2 and BSC.
Fig. 6: In situ formed BSC + PBSCF reduces the positive electrode–electrolyte contact resistance.
Fig. 7: LT-PCECs attain exceptional fuel-cell and electrolysis performance.
Fig. 8: Stability of LT-PCECs with in situ formed BSC + PBSCF as the positive electrode for power generation in fuel-cell mode and green H2 production in electrolysis mode.

Data availability

The data supporting the findings of this study are available within the Article and its Supplementary Information files.


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This work was financially supported by the Nissan Motor Co., Ltd (A22-0455-001, C.D.), Department of Energy grants (DE-FE0032005, DE-SC0021505, DE-FE0032235 and DE-FE0032300, C.D.) and a National Aeronautics and Space Administration grant (80NSSC21C0220, C.D.). Some of the work was performed in following core facility, which is a part of Colorado School of Mines’ Shared Instrumentation Facility (Electron Microscopy: RRID:SCR_022048).

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Authors and Affiliations



Conceptualization: C.D., F.L. Methodology: C.D., F.L., D.D., H.D., B.L. Investigation: C.D., F.L., H.D., D.D., P. Kumar, M.H.A.J., C.G., Y.F., N.D., T.O., M.U., P. Kazempoor, L.F., D.C., B.L. Visualization: C.D., F.L. Funding acquisition: C.D. Project administration: C.D. Supervision: C.D. Writing—original draft: C.D., F.L. Writing—review & editing: C.D., F.L., H.D., D.D., P. Kumar, M.H.A.J., C.G., Y.F., N.D., T.O., M.U., P. Kazempoor, L.F., D.C., B.L.

Corresponding author

Correspondence to Chuancheng Duan.

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Competing interests

Part of this work is financially supported by the Nissan Motor Co., Ltd (A22-0455-001). The funder participates in the decision to publish and preparation of the manuscript. Co-authors M.H.A.J., C.G., Y.F. and N.D. are employed at Nissan Technical Centre North America (NTCNA), Farmington Hills, MI, USA. Co-authors T.O. and M.U. are employed at Nissan Research Center, Nissan Motor Company Limited, Yokosuka, Japan.

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Nature Energy thanks Miguel Laguna-Bercero, Yueh-Lin Lee, Zongping Shao and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.

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Supplementary information

Supplementary Information

Supplementary Notes 1–4, Figs. 1–41, Tables 1–8 and references.

Supplementary Data 1

Atomic coordinates (POSCARs) of bulk structures, structures with oxygen vacancies, and initial and final states of oxygen diffusion calculations OF BSC, PBSCF-1 and PBSCF-2.

Supplementary Video 1

A demonstration of green hydrogen production at 400 °C.

Supplementary Video 2

Button PCEC electrolyte ultrasonic spray coating.

Supplementary Video 3

Large-area PCEC electrolyte ultrasonic spray coating.

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Liu, F., Deng, H., Diercks, D. et al. Lowering the operating temperature of protonic ceramic electrochemical cells to <450 °C. Nat Energy 8, 1145–1157 (2023).

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