title: On an Easy Way To Prepare Metal-Nitrogen Doped Carbon with Exclusive Presence of MeN4-type Sites Active for the ORR.
abstract: Today, most metal and nitrogen doped carbon catalysts for ORR reveal a heterogeneous composition. This can be reasoned by a nonoptimized precursor composition and various steps in the preparation process to get the required active material. The significant presence of inorganic metal species interferes with the assignment of descriptors related to the ORR activity and stability. In this work we present a simple and feasible way to reduce the contribution of inorganic metal species in some cases even down to zero. Such catalysts reveal the desired homogeneous composition of MeN4 (Me = metal) sites in the carbon that is accompanied by a significant enhancement in ORR activity. Among the work of other international groups, our iron-based catalyst comprises the highest density of FeN4 sites ever reported without interference of inorganic metal sites.
authors.affiliation: Institute for Solar Fuels, Helmholtz-Zentrum Berlin für Materialen und Energie , Hahn-Meitner-Platz 1, 14109 Berlin, Germany.|Chair on Catalysts and Electrocatalysts, Graduate School of Excellence Energy Science and Engineering, Departments of Materials and Earth Science and Chemistry, TU Darmstadt , Jovanka-Bontschits-Strasse 2, 64287 Darmstadt, Germany.
authors.forename: Ulrike I
authors.initials: UI
authors.lastname: Kramm
authors.affiliation: Institute for Solar Fuels, Helmholtz-Zentrum Berlin für Materialen und Energie , Hahn-Meitner-Platz 1, 14109 Berlin, Germany.
authors.forename: Iris
authors.initials: I
authors.lastname: Herrmann-Geppert
authors.affiliation: Berlin Joint EPR Laboratory (BeJEL), Department of Physics, Freie Universität Berlin , Arnimallee 14, 14195 Berlin, Germany.
authors.forename: Jan
authors.initials: J
authors.lastname: Behrends
authors.affiliation: Berlin Joint EPR Laboratory (BeJEL), Institute of Nanospectroscopy, Helmholtz-Zentrum Berlin für Materialen und Energie , Albert-Einstein-Str. 15, 12489 Berlin, Germany.
authors.forename: Klaus
authors.initials: K
authors.lastname: Lips
authors.affiliation: Institute for Solar Fuels, Helmholtz-Zentrum Berlin für Materialen und Energie , Hahn-Meitner-Platz 1, 14109 Berlin, Germany.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Fiechter
authors.affiliation: Institute for Solar Fuels, Helmholtz-Zentrum Berlin für Materialen und Energie , Hahn-Meitner-Platz 1, 14109 Berlin, Germany.
authors.forename: Peter
authors.initials: P
authors.lastname: Bogdanoff