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Pyrolyzed base‐metal‐based metal–organic frameworks (MOFs) with FeNx coordination are emerging as nonprecious metal catalysts for electrochemical oxygen reduction reaction (ORR). However, surprisingly, nonpyrolyzed MOFs involving Fe−N coordination have not been explored for the ORR. This study concerns the catalytic performance of a semiconducting nonpyrolyzed iron triazolate framework (FeTa2) for ORR in alkaline electrolyte. The FeTa2 catalyst is studied as composites with different amounts of conductive Ketjenblack carbon (KB). The performance of these FeTa2‐x KB (x denotes the KB/FeTa2 weight ratio) composites by onset and half‐wave potentials of ORR appears to be superior to most previously documented nonpyrolyzed MOFs. Characterization by elemental analysis, FTIR spectroscopy, XPS, and cyclic voltammetry suggest that N−FeIII−OH− sites at the surface of FeTa2 function as the catalytic active sites. This FeTa2 also shows very stable activity during ORR, as supported by accelerated durability test of the FeTa2‐x KB sample (20 000 cycles, ca. 90 h). The framework structure of FeTa2 remains intact during the durability test, which would help to explain its excellent catalytic durability. This would be the first study demonstrating efficient and stable ORR catalysis by a nonpyrolyzed Fe−N coordination‐based MOF material. No heat needed: An iron triazolate framework (FeTa2) featuring Fe−N coordinated sites without further heat treatment is used as an efficient and very stable catalyst for oxygen reduction reaction (ORR). XRD measurements for FeTa2‐2 KB sample (KB=Ketjenblack carbon), before and after an accelerated durability test of 90 hours, unveil that the robust framework enables remarkable ORR durability. [ABSTRACT FROM AUTHOR]

Pyrolyzed base-metal-based metal-organic frameworks (MOFs) with FeN x coordination are emerging as nonprecious metal catalysts for electrochemical oxygen reduction reaction (ORR). However, surprisingly, nonpyrolyzed MOFs involving Fe-N coordination have not been explored for the ORR. This study concerns the catalytic performance of a semiconducting nonpyrolyzed iron triazolate framework (FeTa 2 ) for ORR in alkaline electrolyte. The FeTa 2 catalyst is studied as composites with different amounts of conductive Ketjenblack carbon (KB). The performance of these FeTa 2 -x KB (x denotes the KB/FeTa 2 weight ratio) composites by onset and half-wave potentials of ORR appears to be superior to most previously documented nonpyrolyzed MOFs. Characterization by elemental analysis, FTIR spectroscopy, XPS, and cyclic voltammetry suggest that N-Fe III -OH - sites at the surface of FeTa 2 function as the catalytic active sites. This FeTa 2 also shows very stable activity during ORR, as supported by accelerated durability test of the FeTa 2 -x KB sample (20 000 cycles, ca. 90 h). The framework structure of FeTa 2 remains intact during the durability test, which would help to explain its excellent catalytic durability. This would be the first study demonstrating efficient and stable ORR catalysis by a nonpyrolyzed Fe-N coordination-based MOF material., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)