Synergistically enhanced oxygen reduction activity of iron-based nanoshell carbons by copper incorporation

Critical advancements in achieving high power and stable nonprecious metal catalyst–based MEAs for real-world proton exchange membrane fuel cell applications

“…Mechanism 1 (demetalation) is likely not to be a significant contributor to current generations of NPMCs. This is because most NPMCs (including CA#1 used in this study) are now acid-washed before incorporating into the CCL, which should remove most of the leachable iron ( 41 – 43 ). In addition, recent work has convincingly demonstrated that although demetalation likely does occur, it has no correlation with performance/stability loss within the first several hours (where most of the instability is observed) ( 30 , 34 , 44 ).…”

Bimetallic M/N/C catalysts prepared from π-expanded metal salen precursors toward an efficient oxygen reduction reaction

“…[7][8][9] Catalysts including a rst row transition metal, such as Fe, Cu, or Co, and nitrogen atoms embedded within a carbonaceous structure are known as M/N/C catalysts and have been generally considered to represent promising alternatives to PGM catalysts, because the M/N/C catalysts have been shown to promote high levels of ORR activity while having suitable durability for use in PEFCs. [10][11][12][13][14][15] Pyrolyzed transition metals such as Fe, Cu, and Co in combination with macrocyclic ligands adsorbed on carbon supports have been proven to improve ORR activity and stability under acidic conditions, which is a requirement for PEFCs. 16,17 A series of low-cost nitrogencontaining precursors such as phenanthroline, 11 polypyrrole, 10 and polyaniline 12 have been utilized in preparation of M/N/C catalysts.…”

Nonprecious‐metal Fe/N/C Catalysts Prepared from π‐Expanded Fe Salen Precursors toward an Efficient Oxygen Reduction Reaction

“…This situation has stimulated extensive investigations for the development of alternative low‐cost non‐precious metal catalysts (NPMCs) . Carbon catalysts containing a first row transition metal, such as Fe or Co, and nitrogen (which are known as M/N/C catalysts), have been generally considered as promising alternatives to the PGM catalysts, because the M/N/C catalysts can promote high levels of ORR activity and their durability makes them suitable for use in PEFCs . Studies on M/N/C catalysts were initiated after the discovery of the ORR activity of cobalt phthalocyanine under alkaline conditions .…”