Ice/Salt-Assisted Synthesis of Ultrathin Two-Dimensional Micro/Mesoporous Iron and Nitrogen Co-Doped Carbon as an Efficient Electrocatalyst for Oxygen Reduction

Hanyu Li; Zhengping Zhang; Tomokazu Iyoda; Meiling Dou; Feng Wang

doi:10.1002/chem.201900306

Ice/Salt-Assisted Synthesis of Ultrathin Two-Dimensional Micro/Mesoporous Iron and Nitrogen Co-Doped Carbon as an Efficient Electrocatalyst for Oxygen Reduction

Chemistry. 2019 Apr 17;25(22):5768-5776. doi: 10.1002/chem.201900306. Epub 2019 Mar 21.

Authors

Hanyu Li^{1

2}, Zhengping Zhang^{1

2}, Tomokazu Iyoda³, Meiling Dou^{1

2}, Feng Wang^{1

2}

Affiliations

¹ State Key Laboratory of Chemical Resource Engineering, Laboratory of Electrochemical Process and Technology for Materials, Beijing University of Chemical Technology, Beijing, 100029, China.
² Beijing Advanced Innovation Center for Soft Matter Science, and Engineering, Beijing University of Chemical Technology, Beijing, 100029, China.
³ Harris Science Research Institute, Doshisha University, 1-3 Miyakodani Tatara, Kyotanabe, Kyoto, 611-0394, Japan.

PMID: 30740789
DOI: 10.1002/chem.201900306

Abstract

An ice/salt-assisted strategy has been developed to achieve the green and efficient synthesis of ultrathin two-dimensional (2D) micro/mesoporous carbon nanosheets (CNS) with the dominant active moieties of Fe-N₄ (Fe-N-CNS) as high-performance electrocatalysts for the oxygen reduction reaction (ORR). The strategy involves freeze-drying a mixture of iron porphyrin and KCl salt using ice as template followed by a confined pyrolysis with KCl as an independent sealed nanoreactor to facilitate the formation of 2D carbon nanosheets, N incorporation, and porosity creation. The well-defined assembly of ultrathin 2D carbon nanosheets ensures high utilization of D1 and D3 Fe-N₄ active sites, and effectively promotes the mass transport of ORR reactants by virtue of the pronounced mesoporous structure. The resulting Fe-N-CNS electrocatalyst was shown to exhibit superior ORR activity, better electrochemical durability, and methanol tolerance towards ORR in alkaline electrolyte relative to the commercial Pt/C electrocatalyst.

Keywords: carbon; doping; electrochemistry; oxygen; reduction.

Abstract

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