All-Sputtered, Superior Power Density Thin-Film Solid Oxide Fuel Cells with a Novel Nanofibrous Ceramic Cathode

Yoon Ho Lee; Haowen Ren; Erik A Wu; Eric E Fullerton; Ying Shirley Meng; Nguyen Q Minh

doi:10.1021/acs.nanolett.9b02344

All-Sputtered, Superior Power Density Thin-Film Solid Oxide Fuel Cells with a Novel Nanofibrous Ceramic Cathode

Nano Lett. 2020 May 13;20(5):2943-2949. doi: 10.1021/acs.nanolett.9b02344. Epub 2020 Mar 26.

Authors

Yoon Ho Lee^{1

2}, Haowen Ren³, Erik A Wu⁴, Eric E Fullerton^{3

4

5

6

7}, Ying Shirley Meng^{4

5

6}, Nguyen Q Minh¹

Affiliations

¹ Center for Energy Research, University of California, San Diego, La Jolla, California 92093, United States.
² School of Mechanical Engineering, University of Ulsan, Ulsan 44610, Republic of Korea.
³ Materials Science and Engineering, University of California, San Diego, La Jolla, California 92093, United States.
⁴ Department of Nanoengineering, University of California, San Diego, La Jolla, California 92093, United States.
⁵ Center for Memory and Recording Research, University of California, San Diego, La Jolla, California 92093, United States.
⁶ Sustainable Power and Energy Center (SPEC), University of California, San Diego, La Jolla, California 92093, United States.
⁷ Department of Electrical and Computer Engineering, University of California, San Diego, La Jolla, California 92093, United States.

PMID: 32176514
DOI: 10.1021/acs.nanolett.9b02344

Abstract

Thin film solid oxide fuel cells (TF-SOFCs) are attracting attention due to their ability to operate at comparatively lower temperatures (400-650 °C) that are unattainable for conventional anode-supported SOFCs (650-800 °C). However, limited cathode performance and cell scalability remain persistent issues. Here, we report a new approach of fabricating yttria-stabilized zirconia (YSZ)-based TF-SOFCs via a scalable magnetron sputtering process. Notable is the development and deposition of a porous La_0.6Sr_0.4Co_0.2Fe_0.8O_2.95(LSCF)-based cathode with a unique fibrous nanostructure. This all-sputtered cell shows an open-circuit voltage of ∼1.0 V and peak power densities of ∼1.7 and ∼2.5 W/cm² at 600 and 650 °C, respectively, under hydrogen fuel and air along with showing stable performance in short-term testing. The power densities obtained in this work are the highest among YSZ-based SOFCs at these low temperatures, which demonstrate the feasibility of fabricating exceptionally high-performance TF-SOFC cells with distinctive dense or porous nanostructures for each layer, as desired, by a sputtering process. This work illustrates a new, potentially low-cost, and scalable platform for the fabrication of next-generation TF-SOFCs with excellent power output and stability.

Keywords: Nanofiber; SOFC; Solid oxide fuel cell; Sputtering; Thin film.