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Expedited conversion of O2 to H2O with minimal amounts of Pt is essential for wide applicability of PEM fuel cells (PEMFCs). Therefore, it is imperative to develop a process for catalyst management to circumvent unnecessary catalyst loss while improving the Pt utilization, catalytic activity, and durability. Here, the fabrication of a self‐standing nanofiber electrode is demonstrated by employing electrospinning. This film‐type catalyst simultaneously contains Pt–Co alloy nanoparticles and Co embedded in an N‐doped graphitized carbon (Co–Nx) support derived from the electrospun zeolitic imidazolate frameworks. Notably, the flexible electrode is directly transferrable for the membrane‐electrode assembly of high temperature PEMFC. In addition, the electrodes exhibit excellent performance, maybe owing to the synergistic interaction between the Pt–Co and Co–Nx as revealed by the computational modeling study. This method simplifies the fabrication and operation of cell device with negligible Pt loss, compared to ink‐based conventional catalyst coating methods. [ABSTRACT FROM AUTHOR]

Nanofiber Electrodes: Self-Standing Nanofiber Electrodes with Pt-Co Derived from Electrospun Zeolitic Imidazolate Framework for High Temperature PEM Fuel Cells (Adv. Funct. Keywords: direct transfer; electrospinning; high temperature PEM fuel cell; oxygen reduction reaction; platinum-cobalt EN direct transfer electrospinning high temperature PEM fuel cell oxygen reduction reaction platinum-cobalt 1 1 1 02/12/21 20210210 NES 210210 In article number 2006771, Shao Jing, Wenjing Zhang, and co-workers develop a flexible self-standing nanofiber electrode doped with Pt-Co alloy nanocatalysts via electrospinning. Direct transfer, electrospinning, high temperature PEM fuel cell, oxygen reduction reaction, platinum-cobalt. [Extracted from the article]

[Display omitted] • Method for synthesizing metal-free electrocatalyst with highly ordered nanochannels. • Thermal treatment in NH 3 atmosphere for activation of catalyst surface toward oxygen reduction. • Improved performance after stability test owing to ordered nanostructure with activated surface. • Verification of variations in N-containing species during oxygen reduction reaction. Lowering the cost of electrocatalysts for the oxygen reduction reaction (ORR) is indispensable for the wider commercialization of fuel cells. Therefore, the development of non-Pt, especially metal-free, carbon-based electrocatalysts, has been encouraged as an alternative to Pt. Here, we report active N-doped nanocarbon electrocatalysts in ORR activated by thermal treatment of pristine carbon precursors with highly aligned mesopore channels under an NH 3 atmosphere. This NH 3 -activation process adopts N-containing carbon sites, leading to enhanced ORR performance in an alkaline electrolyte with negligible formation of peroxide species. The stability of the activated carbon electrocatalysts was confirmed by performing 40,000 rounds of potential cycles in the accelerated stress test (AST). The variations in the voltammograms during AST were analyzed using X-ray photoelectron spectroscopy. The correlation between electrochemical behavior and the N 1 s spectrum corroborates the contribution of N-related sites toward voltammetric responses in ORR. [ABSTRACT FROM AUTHOR]