fig3

Figure 3. (A) LSV curves for Fe₂O₃/FeNC in N₂- and Ar-saturated 0.1 M Na₂SO₄; (B) Chronoamperometric curves for Fe₂O₃/FeNC at selected potentials; (C) the UV-vis absorption spectra of the obtained electrolytes, and corresponding NH₃ yields and FEs determined by (D) indophenol blue method and (E) ammonia-selective electrode method (the error line represents the standard deviation); (F) Comparison of electrocatalytic N₂ reduction performance with reported catalysts; (G) UV-vis absorption spectra of the electrolytes after 2 h electrolysis at selected potentials; (H) NH₃ yields of control tests with the inset showing corresponding UV-vis absorption spectra; (I) NH₃ yields and FEs for alternating cycles in Ar- and N₂-saturated 0.1 M Na₂SO₄, respectively. LSV: Linear sweep voltammetry; UV-vis: ultraviolet-visible; FEs: Faradaic efficiencies.