TU Darmstadt / ULB / TUbiblio

Deconvolution of Utilization, Site Density, and Turnover Frequency of Fe–Nitrogen–Carbon Oxygen Reduction Reaction Catalysts Prepared with Secondary N-Precursors

Leonard, Nathaniel D. and Wagner, Stephan and Luo, Fang and Steinberg, Julian and Ju, Wen and Weidler, Natascha and Wang, Huan and Kramm, Ulrike I. and Strasser, Peter (2018):
Deconvolution of Utilization, Site Density, and Turnover Frequency of Fe–Nitrogen–Carbon Oxygen Reduction Reaction Catalysts Prepared with Secondary N-Precursors.
In: ACS Catalysis, ACS Publications, pp. 1640-1647, 8, (3), ISSN 2155-5435, DOI: 10.1021/acscatal.7b02897, [Online-Edition: https://doi.org/10.1021/acscatal.7b02897],
[Article]

Abstract

Metal nitrogen carbon (MNC) catalysts represent a potential means of reducing cathode catalyst costs in low temperature fuel cell cathodes. Knowledge-based improvements have been hampered by the difficulty to deconvolute active site density and intrinsic turnover frequency. In the present work, MNC catalysts with a variety of secondary nitrogen precursors are addressed. CO chemisorption in combination with Mossbauer spectroscopy are utilized in order to unravel previously inaccessible relations between active site density, turnover frequency, and active site utilization. This analysis provides a more fundamental description and understanding of the origin of the catalytic reactivity; it also provides guidelines for further improvements. Secondary nitrogen precursors impact quantity, quality, dispersion, and utilization of active sites in distinct ways. Secondary nitrogen precursors with high nitrogen content and micropore etching capabilities are most effective in improving catalysts performance.

Item Type: Article
Erschienen: 2018
Creators: Leonard, Nathaniel D. and Wagner, Stephan and Luo, Fang and Steinberg, Julian and Ju, Wen and Weidler, Natascha and Wang, Huan and Kramm, Ulrike I. and Strasser, Peter
Title: Deconvolution of Utilization, Site Density, and Turnover Frequency of Fe–Nitrogen–Carbon Oxygen Reduction Reaction Catalysts Prepared with Secondary N-Precursors
Language: English
Abstract:

Metal nitrogen carbon (MNC) catalysts represent a potential means of reducing cathode catalyst costs in low temperature fuel cell cathodes. Knowledge-based improvements have been hampered by the difficulty to deconvolute active site density and intrinsic turnover frequency. In the present work, MNC catalysts with a variety of secondary nitrogen precursors are addressed. CO chemisorption in combination with Mossbauer spectroscopy are utilized in order to unravel previously inaccessible relations between active site density, turnover frequency, and active site utilization. This analysis provides a more fundamental description and understanding of the origin of the catalytic reactivity; it also provides guidelines for further improvements. Secondary nitrogen precursors impact quantity, quality, dispersion, and utilization of active sites in distinct ways. Secondary nitrogen precursors with high nitrogen content and micropore etching capabilities are most effective in improving catalysts performance.

Journal or Publication Title: ACS Catalysis
Volume: 8
Number: 3
Publisher: ACS Publications
Uncontrolled Keywords: oxygen reduction reaction, nonprecious metal catalysts, fuel cells, Mossbauer spectroscopy,electrocatalysis
Divisions: 11 Department of Materials and Earth Sciences
11 Department of Materials and Earth Sciences > Material Science
11 Department of Materials and Earth Sciences > Material Science > Catalysts and Electrocatalysts
Date Deposited: 11 Dec 2018 11:20
DOI: 10.1021/acscatal.7b02897
Official URL: https://doi.org/10.1021/acscatal.7b02897
Funders: U.I.K and S.W. acknowledge financial support by the BMBF via contract 05K16RD1 and by the Graduate School of Excellence Energy Science and Engineering (GRC1070)., P.S. acknowledges support by the European Commission and the Horizon 2020 framework funding under the FCH JU 2 program via the "CRECENDO" project.
Export:

Optionen (nur für Redakteure)

View Item View Item