TY - GEN A1 - Kramm, Ulrike Ingrid A1 - Herrmann-Geppert, Iris A1 - Fiechter, Sebastian A1 - Zehl, Gerald A1 - Zizak, Ivo A1 - Dorbandt, Iris A1 - Schmeißer, Dieter A1 - Bogdanoff, Peter T1 - Effect of iron carbide formation on the number of active sites in Fe-N-C catalysts for the oxygen reduction reaction in acidic media T2 - Journals of materials chemistry A KW - Oxygen reduction reaction (ORR) KW - Fe-N-C catalyst KW - acidic media KW - high-temperature X-ray diffraction (HT-XRD) KW - thermogravimetry coupled with mass-spectroscopy (TG-MS) Y1 - 2014 U6 - https://doi.org/10.1039/c3ta13821f SN - 2050-7488 SN - 2050-7496 IS - 8 SP - 2663 EP - 2670 ER - TY - GEN A1 - Kramm, Ulrike Ingrid A1 - Zana, Alessandro A1 - Vosch, Tom A1 - Fiechter, Sebastian A1 - Arenz, Matthias A1 - Schmeißer, Dieter T1 - On the structural composition and stability of Fe–N–C catalysts prepared by an intermediate acid leaching T2 - Journal of Solid State Electrochemistry N2 - The development of highly active and stable non-noble metal catalysts (NNMC) for the oxygen reduction reaction (ORR) in proton exchange membrane fuel cells (PEM-FC) becomes of importance in order to enable cost reduction. In this work, we discuss the structural composition as derived from Fe-57Mößbauer spectroscopy and X-ray diffraction, catalytic performance determined by a rotating (ring)disk electrode (RRDE) technique and stability evaluation of our Fe–N–C catalysts prepared by an intermediate acid leaching (IAL). The advantage of this IAL is given by a high density of active sites within the catalyst, as even without sulphur addition, an iron carbide formation and related disintegration of active sites are inhibited. In addition, our accelerated stress tests illustrate better stability of the sulphur-free IAL catalyst in comparison to the sulphur-added one. KW - Non-noblemetal catalysts (NNMC) KW - Fe–N–C KW - oxygen reduction reaction (ORR) KW - PEM fuel cell (PEM-FC) KW - Accelerated stress tests (ASTs) KW - Mößbauer spectroscopy Y1 - 2016 U6 - https://doi.org/10.1007/s10008-015-3060-z SN - 1432-8488 SN - 1433-0768 N1 - 1. ISSN: P 2. ISSN: E VL - 20 IS - 4 SP - 969 EP - 981 ER -