A plasma-assisted approach to enhance density of accessible FeN4 sites for proton exchange membrane fuel cells

Designed Synthesis and Electrochemical Performance Regulation of the Hierarchical Hollow Structure Cu2S/Cu7S4/NC Anode for Hybrid Supercapacitors

“…The peaks indicate that the main form of sulfur element in the composites is S 2– . , The peak centered at about 163.5 eV could be attributed to the C–S–C bonds. As shown in Figure e, the C 1s spectrum could be fitted into two peaks at 284.8 and 286.0 eV, corresponding to the sp 2 C–C and C–O bonds. , As shown in Figure f, the high-resolution XPS spectrum of N 1s could be fitted into two peaks. The peak at 398.8 eV indicates the pyridine nitrogen, and the peak at 401.0 eV represents the quaternary nitrogen.…”

“…As shown in Figure 2e, the C 1s spectrum could be fitted into two peaks at 284.8 and 286.0 eV, corresponding to the sp 2 C−C and C−O bonds. 33,34 As shown in Figure 2f, the high-resolution XPS spectrum of N 1s could be fitted into two peaks. The peak at 398.8 eV indicates the pyridine nitrogen, and the peak at 401.0 eV represents the quaternary nitrogen.…”

Plasma Technology Applications in Proton Exchange Membrane Fuel Cell Systems

“…This is attributed to its substantial specific surface area, abundant active sites, and well-structured pore configurations. [36] Li et al [37] enhanced the density and utilization of FeN 4 active sites through plasma treatment, thereby improving the ORR catalytic activity of the FeÀ NÀ C catalyst in acidic environments. Their approach encompassed several key steps: Initially, a high-microporous nitrogen-carbon catalyst (NC) was obtained by calcining ZIF-8 (zeolitic imidazolate framework) in an Ar atmosphere at 1000 °C.…”

Regulation Strategies for Fe−N−C and Co−N−C Catalysts for the Oxygen Reduction Reaction

“…In MÀ NÀ C catalysts, MÀ N X sites serve as active centers and are embedded in the graphitized carbon layer. Therefore, the structure of the carbon support has always been considered to have an important influence on the oxygen reduction performance of MÀ NÀ C. [77][78][79][80] In recent years, the bending of carbon supports has received widespread attention as another important factor that can significantly affect the ORR performance of MÀ N X sites. [81][82][83] Qu et al [84] achieved in-situ growth of N-doped carbon nanotubes during the synthesis process of the CoÀ NÀ C catalyst by precisely controlling the ratio of metal ions to 2methylimidazole during the synthesis process (Figure 6a).…”

“…Compared with micropores, the moderate pore size range of mesopores (2-50 nm) can ensure the exposure of Fe/ CoÀ N X sites and the transport of O 2 during the reaction process. [23,79,[103][104] Therefore, increasing the proportion of mesopores in the catalyst can improve the structure of carbon layers and build transport channels for reactants and products. Wang et al [77] used ZIF-8 precursor to prepare mesoporous N-doped carbon supports through molten salt-assisted pore creation, and further adsorbed Fe 3 + for secondary pyrolysis to prepare FeÀ NÀ C catalyst with an ASD of up to 26.3×10 19 sites g À 1 .…”