Engineering Atomic Single Metal-FeN4Cl Sites with Enhanced Oxygen-Reduction Activity for High-Performance Proton Exchange Membrane Fuel Cells

Shichao Ding; Jordan Alysia Barr; Qiurong Shi; Yachao Zeng; Peter Tieu; Zhaoyuan Lyu; Lingzhe Fang; Tao Li; Xiaoqing Pan; Scott P Beckman; Dan Du; Hongfei Lin; Jin-Cheng Li; Gang Wu; Yuehe Lin

doi:10.1021/acsnano.2c06459

Engineering Atomic Single Metal-FeN₄Cl Sites with Enhanced Oxygen-Reduction Activity for High-Performance Proton Exchange Membrane Fuel Cells

ACS Nano. 2022 Sep 27;16(9):15165-15174. doi: 10.1021/acsnano.2c06459. Epub 2022 Sep 12.

Authors

Shichao Ding¹, Jordan Alysia Barr¹, Qiurong Shi², Yachao Zeng², Peter Tieu³, Zhaoyuan Lyu¹, Lingzhe Fang⁴, Tao Li^{4

5}, Xiaoqing Pan⁶, Scott P Beckman¹, Dan Du¹, Hongfei Lin⁷, Jin-Cheng Li¹, Gang Wu², Yuehe Lin¹

Affiliations

¹ School of Mechanical and Materials Engineering, Washington State University, Pullman, Washington 99164, United States.
² Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York, Buffalo, New York 14260, United States.
³ Department of Chemistry, University of California, Irvine, Irvine, California 92697, United States.
⁴ Department of Chemistry and Biochemistry, Northern Illinois University, DeKalb, Illinois 60115, United States.
⁵ X-ray Science Division, Argonne National Laboratory, Lemont, Illinois 60439, United States.
⁶ Irvine Materials Research Institute (IMRI), University of California, Irvine, Irvine, California 92697, United States.
⁷ Voiland School of Chemical Engineering and Bioengineering, Washington State University, Pullman, Washington 99164, United States.

PMID: 36094168
DOI: 10.1021/acsnano.2c06459

Abstract

Fe-N-C single-atomic metal site catalysts (SACs) have garnered tremendous interest in the oxygen reduction reaction (ORR) to substitute Pt-based catalysts in proton exchange membrane fuel cells. Nowadays, efforts have been devoted to modulating the electronic structure of metal single-atomic sites for enhancing the catalytic activities of Fe-N-C SACs, like doping heteroatoms to modulate the electronic structure of the Fe-N_x active center. However, most strategies use uncontrolled long-range interactions with heteroatoms on the Fe-N_x substrate, and thus the effect may not precisely control near-range coordinated interactions. Herein, the chlorine (Cl) is used to adjust the Fe-N_x active center via a near-range coordinated interaction. The synthesized FeN₄Cl SAC likely contains the FeN₄Cl active sites in the carbon matrix. The additional Fe-Cl coordination improves the instrinsic ORR activity compared with normal FeN_x SAC, evidenced by density functional theory calculations, the measured ORR half-wave potential (E_1/2, 0.818 V), and excellent membrane electrode assembly performance.

Keywords: Fe−N−C; fuel cells; heteroatoms; oxygen reduction; single-atom catalysts.