ABSTRACT Over the past several years, important strides have been made in demonstrating protonic ceramic fuel cells (PCFCs). Such fuel cells offer the potential of environmentally

sustainable and cost-effective electric power generation. However, their power outputs have lagged behind predictions based on their high electrolyte conductivities. Here we overcome PCFC

performance and stability challenges by employing a high-activity cathode, PrBa0.5Sr0.5Co1.5Fe0.5O5+δ (PBSCF), in combination with a chemically stable electrolyte, BaZr0.4Ce0.4Y0.1Yb0.1O3

(BZCYYb4411). We deposit a thin dense interlayer film of the cathode material onto the electrolyte surface to mitigate contact resistance, an approach which is made possible by the proton

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1322–1330 (2007). Article  Google Scholar  Download references ACKNOWLEDGEMENTS This research was funded in part by the US Department of Energy, through ARPA-e Contract DE-AR0000498, via

subcontract from United Technologies Research Center, and by the National Science Foundation, DMR-1505103. Selected facilities used were supported by the National Science Foundation via

Northwestern University’s MRSEC, DMR-1121262. AUTHOR INFORMATION AUTHORS AND AFFILIATIONS * Materials Science and Engineering, Northwestern University, Evanston, IL, USA Sihyuk Choi, Chris

J. Kucharczyk, Ho-Il Ji & Sossina M. Haile * Applied Physics & Materials Science, California Institute of Technology, Pasadena, CA, USA Chris J. Kucharczyk & Ho-Il Ji * Materials

Science and Engineering, University of Maryland, College Park, MD, USA Yangang Liang, Xiaohang Zhang & Ichiro Takeuchi Authors * Sihyuk Choi View author publications You can also search

for this author inPubMed Google Scholar * Chris J. Kucharczyk View author publications You can also search for this author inPubMed Google Scholar * Yangang Liang View author publications

You can also search for this author inPubMed Google Scholar * Xiaohang Zhang View author publications You can also search for this author inPubMed Google Scholar * Ichiro Takeuchi View

author publications You can also search for this author inPubMed Google Scholar * Ho-Il Ji View author publications You can also search for this author inPubMed Google Scholar * Sossina M.

Haile View author publications You can also search for this author inPubMed Google Scholar CONTRIBUTIONS S.M.H led the development of the concept, guided the experimental design, and

supervised the research. S.C. developed the materials, fabricated the cells, and performed the following experiments and analyses: conductivity, thermogravimetry, fuel cell polarization, and

impedance spectroscopy. Y.L. and X.Z. prepared and characterized PLD microdot electrodes, on which C.J.K. performed electrochemical measurements. I.T. supervised PLD film growth and

characterization. H.-I. J. provided critical suggestions for experimental and analytical methods. S.M.H. and S.C. wrote the paper with contributions from all authors. CORRESPONDING AUTHOR

Correspondence to Sossina M. Haile. ADDITIONAL INFORMATION PUBLISHER’S NOTE: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional

affiliations. SUPPLEMENTARY INFORMATION SUPPLEMENTARY INFORMATION Supplementary Figures 1–15, Supplementary Table 1 and Supplementary References RIGHTS AND PERMISSIONS Reprints and

permissions ABOUT THIS ARTICLE CITE THIS ARTICLE Choi, S., Kucharczyk, C.J., Liang, Y. _et al._ Exceptional power density and stability at intermediate temperatures in protonic ceramic fuel

cells. _Nat Energy_ 3, 202–210 (2018). https://doi.org/10.1038/s41560-017-0085-9 Download citation * Received: 18 August 2017 * Accepted: 18 December 2017 * Published: 12 February 2018 *

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