Tuned Electrospun Fe-NC Catalysts Boost Oxygen Reduction Reaction Performance

Iron-nitrogen-carbon (Fe-NC) catalysts fabricated through electrospinning achieve enhanced oxygen reduction reaction activity and long-term durability compared to commercial platinum-carbon materials. The fabrication process relies directly on controlling both the iron-to-nitrogen precursor ratio and the annealing temperature during thermal processing. The reported experimental findings show that the iron-to-nitrogen precursor ratio and the annealing temperature operate synergistically to regulate the content of different nitrogen species within the resulting electrospun catalyst structures.

The experimental results are consistent with FeN₄ serving as the dominant active site for the oxygen reduction reaction. By tuning the precursor ratio and the annealing temperature, the maximum content of FeN₄ reached 28 percent. This maximum content of 28 percent directly contributes to the excellent catalytic activity observed in the electrospun Fe-NC materials, confirming the critical role of FeN₄ sites in driving the reaction.

Electrochemical performance testing indicates that the optimized Fe-NC catalyst displays better oxygen reduction performance than commercial platinum-carbon (PtC), achieving an improved half-wave potential of E₁/₂ = 0.87 V. In addition to this higher catalytic activity, the optimized catalyst displays better long-term durability than commercial PtC, demonstrating a retention of 76.4 percent under testing conditions. The electrospun catalyst thus surpasses the commercial PtC benchmark in both oxygen reduction performance and durability retention.

Overall, the work provides an effective strategy for designing high-performance Fe-NC electrocatalysts through the precise regulation of nitrogen species. By demonstrating that the iron-to-nitrogen precursor ratio and annealing temperature synergistically regulate nitrogen species and maximize the active FeN₄ content at 28 percent, the study presents an effective method for enhancing both catalytic activity and long-term durability relative to commercial PtC.

Subject of Research: Electrospun Fe-NC electrocatalysts for the oxygen reduction reaction

Article Title: Electrospun Fe-NC catalysts: tuning Fe/N ratio and annealing temperature to regulate nitrogen species for enhanced oxygen reduction reaction

Article References: Li, Z., Li, C., Gao, P., Yu, H., Shu, Q., Zhang, Y., Liu, S., & Zhao, H. (2026). Electrospun Fe-NC catalysts: tuning Fe/N ratio and annealing temperature to regulate nitrogen species for enhanced oxygen reduction reaction. Ionics. https://doi.org/10.1007/s11581-026-07621-w

Image Credits: AI Generated

DOI: 10.1007/s11581-026-07621-w

Keywords: Fe-NC catalysts, electrospinning, oxygen reduction reaction, electrocatalysis, nitrogen species, FeN4 active sites, annealing temperature, catalytic durability, Electrospun, Fe-NC, catalysts, tuning