{'fraction_non_alphanumeric': 0.041294642857142856, 'fraction_numerical': 0.017857142857142856, 'mean_word_length': 4.901315789473684, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Fe-N4 Doped Carbon Nanotube Cathode Catalyst for PEM Fuel Cells.

The earth-abundant iron and nitrogen doped carbon (Fe-N-C) catalyst has great potential to substitute noble metal catalysts for oxygen reduction reaction (ORR) in H2-O2 proton exchange membrane fuel cells (PEMFCs). Herein, we report the preparation of Fe-N4 moiety doped carbon nanotubes (CNTs) by ball milling and two-step pyrolysis with dual metal-organic frameworks (MOFs) as the precursor. This catalyst shows high ORR catalytic performance and stability. Different from traditional inorganic iron sources, the MOF structure can effectively prevent the iron metal from aggregating during pyrolysis. In PEMFC, the catalyst shows high current density (0.39 A/cm2 at 0.7 V) and power density (850 mW/cm2). Such a method brings inspiration for the reasonable design of FeNC catalysts with high catalytic activity for H2-O2 PEMFCs.